Digital PDFs

EK-DEQNA-UG-001

May 1984

85 pages

Original

3.2MB

Document:	DEQNA ETHERNET User's Guide
Order Number:	EK-DEQNA-UG
Revision:	001
Pages:	85
Original Filename:	http://bitsavers.org/pdf/dec/qbus/EK-DEQNA-UG-001.pdf

OCR Text

EK-DEQNA-UG-001

DEQNA ETHERNET
User's Guide

EK-DEQNA-UG-001

DEQNA ETHERNET
User's Guide

Prepared by Educational Services
of
Digital Equipment Corporation

I st Edition, August, 1984

All Rights Reserved.
Printed in U.s.A.
NOTE: Multiple DEQNAs may not be configured in
the same CPU cabinet. Such a configuration exceeds
current Federal guidelines regarding emissions of
RFI/EMI and thus cannot be either system integrated or warranted by Digital Equipment Corporation.
Customers may, at their discretion, order and
upgrade their systems with multiple DEQNAs in the
same CPU cabinet. However, if multiple DEQNAs
are integrated by a customer, it is the customer's
responsibility to conform to Federal FRI/EMI emission guidelines.
The information in this document is subject to
change without notice. Digital Equipment Corporation assumes no responsibility for any errors that
may appear in this manual.
The software described in this document is furnished
under a license and may not be used or copied except
in accordance with the terms of such license.
Digital Equipment Corporation assumes no responsibility for the use or reliability of its software on
equipment that is not supplied by Digital.
The following are trademarks of Digital Equipment
Corporation:

!amaamD™
DEC
DECmate
DEC net
DECsystem-IO
DECSYSTEM-20
DECUS
DECwriter

DIBOL
MASSBUS
PDP
P/OS
Q-Bus
Professional
Rainbow
RSTS

RSX
TOPS-I 0
TOPS-20
UNIBUS
VAX
VMS
VT
Work Processor

CONTENTS
Page
CHAPTER 1

INTRODUCTION

1.1
1.1.1
1.1.1.1
1.2
1.2.1
1.2.2
1.2.3
1.2.4
1.3
1.3.1
1.3.2
1.3.2.1
1.3.3
1.3.3.1
1.3.3.2
1.3.3.3
1.3.4
1.3.4.1
1.3.4.2
1.3.4.3
1.3.4.4
1.3.5
1.3.6
1.3.7
1.4
1.4.1
1.4.2
1.5
1.6

ETHERNET OVERVIEW ........................................................................................ 1-1
ETHERNET Layers .......................................................................................... 1-3
Data Encapsulation .................................................................................... 1-3
DEQNA DESCRIPTION .......................................................................................... 1-4
Q-Bus DMA Transfer Controller (QDTC) ........................................................ 1-6
Receive FIFO ..................................................................................................... 1~6
ETHERNET Protocol Processor (EPP) ............................................................ 1-6
Encoder/Decoder (ED) ...................................................................................... 1-7
DEQNA SYSTEM OPERATION ............................................................................ 1-7
Port Registers ..................................................................................................... 1-7
Host Communications Area ............................................................................... 1-8
Buffer Descriptor List (BDL) .................................................................... 1-8
Initialization ........................................................................................................ 1-8
Bootstrap .................................................................................................... 1-9
Receiver Enable ......................................................................................... 1-9
Interrupt Vector ......................................................................................... 1-9
Loopback ............................................................................................................ 1-9
Set-Up Mode ............................................................................................ 1-10
Internal Loopback (lLOOP) .................................................................... 1-10
External Loopback (ELOOP) .................................................................. 1-10
Internal Extended Loopback (IELOOP) ................................................. 1-10
Sanity Timer ..................................................................................................... 1-11
Transmit ........................................................................................................... 1-11
Receive ............................................................................................................. 1-12
Q-BUS INTERFACE .............................................................................................. 1-13
Slave Logic ....................................................................................................... 1-13
Master Logic .................................................................................................... 1-13
DEQNA SPECIFICATIONS .................................................................................. 1-13
RELATED DOCUMENTS ..................................................................................... 1-14

CHAPTER 2

INSTALLATION

2.1
2.2
2.2.1
2.2.2
2.2.3
2.2.4
2.3
2.3.1
2.3.2
2.3.2.1

UNPACKING AND INSPECTION ........................................................................ 2-1
PREINST ALLATION VERIFICATION ................................................................ 2-2
Host Boot/Diagnostic ROMs ............................................................................. 2-2
Backplane Requirements .................................................................................... 2-2
Bus Latency Constraints .................................................................................... 2-2
Loading Requirements ....................................................................................... 2-2
PREPARATION ....................................................................................................... 2-3
Backplane ........................................................................................................... 2-3
M7504 Module .......... ", ... ,.......... ,.................... ,.................................................. 2-4
Device Address Assignment (Wl) ............................................................. 2-4

iii

CONTENTS (Cont)
Page
2.3.2.2
2.3.2.3
2.3.3
2.4
2.5
2.5.1
2.5.2
2.5.3

Bus Request Holdoff Timer (W2) ............................................................. 2-4
Sanity Timer (W3) .................................................................................... 2-4
Patch and Filter Panel Assembly ...................................................................... 2-4
INSTALLATION ...................................................................................................... 2-4
TESTING ................................................................................................................... 2-6
Post-Installation Power Checks .......................................................................... 2-6
Light-Emitting Diode (LED) Checks ................................................................. 2-6
Diagnostic Acceptance Procedure ...................................................................... 2-7

CHAPTER 3

SERVICE

3.1
3.2
3.2.1
3.2.2
3.2.2.1
3.2.2.2
3.2.3
3.2.3.1
3.2.3.2
3.2.3.3
3.2.3.4
3.2.4
3.2.4.1
3.2.4.2
3.2.4.3
3.3

MAINTENANCE PHILOSOPHy ........................................................................... 3-1
DIAGNOSTICS ......................................................................................................... 3-1
Extended Primary Bootstrap (EPB) ................................................................... 3-1
Citizenship Test (CQ) ........................................................................................ 3-2
Test Descriptions ........................................................................................ 3-2
Test Results ................................................................................................ 3-5
Field Functional Test ......................................................................................... 3-7
Configuration and Set-Up .......................................................................... 3-8
Test Descriptions ........................................................................................ 3-9
Operation .................................................................................................. 3-12
Error Reporting ....................................................................................... 3-14
DEQNA DEC/XII Exerciser ......................................................................... 3-15
Configuration and Set-Up ........................................................................ 3-15
Commands ............................................................................................... 3-16
Error Messages ......................................................................................... 3-16
CORRECTIVE MAINTENANCE ........................................................................ 3-17

CHAPTER 4

PROGRAMMING

4.1
4.2
4.2.1
4.2.2
4.2.3
4.2.4
4.3
4.3.1
4.3.2
4.3.2.1
4.3.2.2
4.3.2.3
4.3.2.4
4.3.2.5
4.3.3
4.3.3.1
4.3.3.2
4.3.3.3

OVERVIEW ............................................................................................................... 4-1
CONTROL AND STATUS TRANSFERS ............................................................. 4-1
Station Address Registers .................................................................................. 4-2
BDL Starting Address Registers ........................................................................ 4-2
Vector Address Register .................................................................................... 4-3
Control and Status Register (CSR) ................................................................... 4-3
DMA TRANSFERS .................................................................................................. 4-6
Buffer Descriptor List (BDL) ............................................................................. 4-6
Buffer Descriptor ................................................................................................ 4-6
Flags ........................................................................................................... 4-6
Address ....................................................................................................... 4-7
Address Descriptor Bits ............................................................................. 4-7
Buffer Length (Word Count) .................................................................... 4-8
Status Words .............................................................................................. 4-8
Set-Up Mode .................................................................................................... 4-11
Target Address Set-Up ............................................................................ 4-11
Operating Condition Set-Up .................................................................... 4-12
Set-Up Packet .......................................................................................... 4-12

APPENDIX A

GLOSSARY

APPENDIX B

VECTOR AND I/O PAGE ADDRESS ASSIGNMENTS

APPENDIX C

NETWORK INTERCONNECT EXERCISER (NIE)

C.1
C.2
C.2.1
C.2.I.1
C.2.1.2
C.2.1.3
C.2.1A
C.2.2
C.3
CA
CA.1
C.4.I.1
CA.1.2
CA.I.3
CA.2
C.S
C.S.1
C.S.I.1
C.S.I.2
C.S.I.3
C.S.2

INTRODUCTION .................................................................................................... C-1
OPERATING MODES ............................................................................................ C-1
Unattended Mode .............................................................................................. C-1
Build Node Table ...................................................................................... C-2
Direct Loop Message Test ........................................................................ C-2
Pattern Test .............................................................................................. C-2
Multiple Message Activity Test.. .............................................................. C-2
Operator Directed Mode ................................................................................... C-2
SYSTEM REQUIREMENTS .................................................................................. C-3
COMMAND DESCRIPTION ................................................................................. C-3
DRS Commands ................................................................................................ C-3
Switches ..................................................................................................... C-4
Flags .......................................................................................................... C-S
Hardware and Software Questions ........................................................... C-6
NIE Commands ................................................................................................ C-6
ERRORS ................................................................................................................. C-13
Error Messages ................................................................................................ C-13
General .................................................................................................... C-13
Basic ........................................................................................................ C-13
Extended ................................................................................................. C-13
Other Error Messages ..................................................................................... C-1S

FIGURES
Figure No.
1-1
1-2
1-3
1-4
l-S
1-6
2-1
2-2
3-1
3-2
3-3
4-1
4-2
4-3
C-1
C-2
C-3
C-4

Title

Page

Large-Scale ETHERNET Configuration ................................................................... 1-2
ETHERNET Layer Functions ................................................................................... 1-3
ETHERNET Packet (Frame) Format ....................................................................... 1-3
DEQNA to ETHERNET Connection ....................................................................... l-S
DEQNA Major Functional Areas .............................................................................. 1-6
BDL Format ............................................................................................................... 1-8
Patch and Filter Panel Assembly ............................................................................... 2-4
M70S4 Showing Jumpers, LEDs, Transceiver Cable Connector,
Station Address PROM, and Boot/Diag PROM ...................................................... 2-S
General Error Message Format. ............................................................................... 3-14
Typical Extended Error Message Format. ............................................................... 3-14
DEQNA DEC/X 11 Exerciser Error Message Format ........................................... 3-16
Port Registers ............................................................................................................. 4-2
BDL Format ............................................................................................................... 4-6
Target Address Set-Up ............................................................................................. 4-11
Loop Direct Message Test Path .............................................................................. C-10
Transmit Assist Loopback Message Test Path ....................................................... C-10
Receive Assist Loopback Message Test Path ......................................................... C-11
Full Assist Loopback Message Test Path ............................................................... C-l1

TABLES
Table No.
1-1
1-2
2-1
2-2
2-3
2-4
2-5
3-1
3-2
3-3
4-1
4-2
4-3
B-1
B-2
B-3
B-4
C-1
C-2
C-3
C-4
C-5
C-6

Title

Page

DEQNA Specifications ............................................................................................ 1-14
Related Documents ................................................................................................... 1-14
DEQNA Parts List ..................................................................................................... 2-2
DEQNA Q-Bus Loading ............................................................................................ 2-3
DEQNA Power Requirements ................................................................................... 2-3
DEQNA Jumper Functions ........................................................................................ 2-5
DEQNA LED Indications .......................................................................................... 2-6
ZQNA Tested Functional Areas ................................................................................ 3-8
Sanity Timer Time-Out Values ................................................................................ 3-13
DEQNA DEC/XII Exerciser Software Register Bits ............................................ 3-16
Flag Word Bits 15 and 14 .......................................................................................... 4-6
Valid and Chain Address Descriptor Bits .................................................................. 4-7
Status Word 1 Bits 15 and 14 ................................................................................... 4-8
Interrupt and Trap Vector Assignments .................................................................... B-1
I/O Page Addresses .................................................................................................... B-2
Floating Vector Rank ................................................................................................. B-3
Floating Address Rank ............................................................................................... B-3
DRS Commands ........................................................................................................ C-3
DRS Command Switches .......................................................................................... C-4
Switch Application ..................................................................................................... C-4
DRS Command Flags ................................................................................................ C-5
NIE Test Message Types .......................................................................................... C-8
Node Pair Array ...................................................................................................... C-12

CHAPTER 1
INTRODUCTION

This chapter introduces the Digital ETHERNET Q-Bus Network Adapter (DEQNA), the M7504 module. The chapter includes an- overview of the ETHERNET and a brief description of the DEQNA, its
operation, and its specifications. The reader who wants more information about the ETHERNET may
refer to a list of related documents in Table 1-2, and the ordering information contained in the last section
of this chapter.
1.1 ETHERNET OVERVIEW
The ETHERNET is a network that supports high-speed data exchange among computers and other digital
devices, within a limited geographic area. The branching bus topology of the ETHERNET provides a 10
Mbits/s (10 megabits per second) data rate over a coaxial cable at a distance of 2.8 kilometers (1. 74 miles)
or less. The ETHERNET is a local area network, with a higher data rate than low-speed networks, which
carry data hundreds or thousands of kilometers, and a greater distance than very high-speed interconnects,
which are usually limited to tens of meters.

The primary applications for the ETHERNET are office automation, distributed data processing, terminal access, and other applications which require an economical local medium for exchanging data at high
peak-data rates. The major characteristics of the ETHERNET are as follows.
Topology:

Branching Bus

Medium:

Shielded coaxial cable. Manchester-encoded digital base-band
signalling

Data Rate:

10 megabits per second

Node Separation:

2.8 kilometers (1.74 miles), maximum

Number of Nodes:

1,024 maximum

Network Control:

Multiaccess - fairly distributed to all nodes

Access Control:

Carrier Sense, Multiple Access with Collision Detect
(CSMA/CD)

Allocation:

64- to I5I8-byte packet length (includes variable length data
field of 45 to 1500 bytes)

As many as 1,024 nodes can be connected together in a local point-to-point/multipoint configuration with
a single ETHERNET. Figure 1-1 is an example of a large-scale ETHERNET configuration. The
ETHERNET configuration rules ensure the best network performance within physical channel limitations. The parameters for a maximum ETHERNET configuration are the following.

1-1

A cable segment is a coaxial cable terminated in its characteristic impedance at both ends. The
maximum length of a segment is 500 meters (1640.5 feet).

Up to 100 nodes can be connected to any segment of the cable. The minimum distance between
nodes on a cable segment is 2.5 meters (8.2 feet).

Repeaters connect segments to extend the cable. Repeaters do not have to be connected at the
ends of a segment; they can occupy any node position; however, there can be no more than two
repeaters in the path between any two nodes. Repeaters are included in the maximum node
count.

The maximum length of coaxial cable between any two nodes is 1500 meters (4921.5 feet).

The maximum length of transceiver cable between a node and its transceiver is 50 meters
(164.05 feet).

The maximum length of a point-to-point (that is, repeater-to-repeater) link is 1000 meters (3281
feet). (See Figure 1-1.)
TRANSCEIVER CABLE

REMOTE
REPEATER

MA-12463

Figure 1-1

Large-Scale ETHERNET Configuration
1-2

1.1.1 ETHERNET Layers
The ETHERNET architecture consists of two layers.

•
•

Data Link Layer
Physical Layer

These layers correspond to the lowest architectural layers in the International Standards Organization
(ISO) Model for Open Systems Interconnection, and are intended to support higher layers of network
architectures. The layer functions are shown in Figure 1-2.
HIGHER LAYERS

DATA ENCAPSULATION

DATA DECAPSULATION

LINK MANAGEMENT

DATA LINK LAYER

I
+

DATA ENCODING

DATA DECODING

CHANNEL ACCESS

PHYSICAL LAYER

TRANSMIT

RECEIVE

I
ETHERNET CABLE

"'-

~---V
MA-12436

Figure 1-2

ETHERNET Layer Functions

1.1.1.1 Data Encapsulation - In the ETHERNET, data is transmitted in packets (also called frames)
with a specific format, as shown in Figure 1-3.
1 FRAME
A.

PREAMBLE

DEST_
ADDRESS

SOURCE
ADDRESS

DATA

TYPE

FRAME
CHECK
SEG_

l
INTERFRAME
SPACING

---l
64 BITS

48 BITS

16 BITS

46 TO 1500 BYTES

32 BITS

9_61Ls
MA-12464

Figure 1-3

ETHERNET Packet (Frame) Format

1-3

A packet begins with a 64-bit preamble. The preamble is a pattern of alternating Is and Os, for receiving
node synchronization. To mark the end of the preamble, the pattern ends with ... 01011, rather than
... 01010.
The destination field contains the 48-bit address of the receiving node(s). The address is either a physical
address or logical address, and can be one of the following.
1.
2.
3.

An individual node address (first address bit = 0).
A multicast address for a group of nodes (first address bit = 1).
A broadcast address to all nodes (all address bits = 1).

The source field contains the 48-bit sending node's address. This is either a physical address or logical
address. The physical address is the default address, set during manufacture and unique to a node.
Software can override the physical address, inserting another physical address into the source field upon
packet transmission.
The 16-bit type field determines how higher architectural layers interpret the data field.
The data field must contain at least 46 bytes but no more than 1500 bytes. If the data to be sent consists of
less than 46 bytes, software must insert null bytes to fill the field.
The frame check sequence contains a 32-bit Cyclic Redundancy Check (CRC) value. The DEQNA
calculates this value inserting it upon packet transmission, and checking it upon packet reception.
The interframe spacing, also called the Inter-Packet Gap (IPG) allows the physical channel to recover
between packets. It must be at least 9.6 microseconds, but no more than 10.6 microseconds.
1.2 DEQNA DESCRIPTION
The DEQNA Q-Bus (LSI-II bus) data communications controller interfaces the Digital Equipment
Corporation LSI-II processor family to the ETHERNET local area network. It works with both I8-bit
address and 22-bit address memories. The DEQNA conforms to the ETHERNET specification, Version
2.0, performing the data link layer functions, and part of the physical layer functions. (See Figure 1-2.)
The DEQNA has the following features.
1.

Transmits and receives data at a rate of 10 Mbits/s.

Recognizes heartbeat and collision detection.

Performs packet serialization, formatting, Manchester encoding, and multiple retransmission.

Generates and checks 32-bit CRC.

Interfaces with the H4000 ETHERNET transceiver.

Performs Direct Memory Access (DMA) transfers to and from CPU memory.

Contains quick-verify diagnostics for power-up and boot.

Performs internal and externalloopback, and can assist on loopback of data from other stations.

Supports host system identification response.

10.

Supports host down-line load and remote boot by other nodes on the network.
1-4

The DEQNA comprises one dual LSI-II module. It plugs into the Q-Bus backplane and resides in the
same enclosure. The DEQNA is physically and electrically connected to the H4000 transceiver as shown
in Figure 1-4.
FACTORY INSTALLED SYSTEM OPTION NUMBER
DEONA-KP (INCLUDES THE CABINET KIT)

ETHERNET
TRANSCEIVER
CABLE

I
I
I
I
I
I
I

H4000 TRANSCEIVER

HOS~ -

-- -

-- --

BULKHEAD I/O
PANEL ASSEMBLY

V B

J1
DEONA
(M7504)

A A

L-,....._-_-_-_-_ _______ _
~

Figure 1-4

DEQNA to ETHERNET Connection

The DEQNA has four major functional areas as shown in Figure 1-5. Each functional area is defined in
the following subsections.

1-5

ETHERNET CABLE

'-r---J.--_ - - - - - - - - - - - l
I
I
I
I
I
L_

ENCODER/
DECODER
(ED)

ETHERNET
PROTOCOL
PROCESSOR
(EPP)

RCV

I
I

RECEIVE
FIFO
(XMIT BUFFER)

XMT

I
I

Q-BUS DMA
TRANSFER
CONTROLLER

(QDTC)

----------~~
HOST
PROCESSOR

Q-BUS

MR-12438

Figure 1-5

DEQNA Major Functional Areas

1.2.1 Q-Bus DMA Transfer Controller (QDTC)
The QDTC moves ETHERNET frames and DEQNA control frames between the DEQNA and host
memory. It comprises bus transceivers, interrupt control logic, Q-Bus control logic, a DMA registers and
counters chip (DMARC), and other control logic. The QDTC performs the host interrupt and DMA
transfer functions.
1.2.2 Receive FIFO
The receive FIFO (First-In/First-Out) is a 4 K X 9-bit RAM. Its usable length for received data is
essentially variable from 2 Kbytes to 3565 bytes. In addition to received data, transmit status and receive
status are queued in the receive FIFO for transfer to the host.
1.2.3 ETHERNET Protocol Processor (EPP)
The EPP performs the data link layer functions of link management and data encapsulation/decapsulation. The EPP comprises an Ethernet Data Link Controller (EDLC), a transmit prefill
RAM, node address compare logic, and control logic. The EPP performs the following functions.
1.

Buffers parallel transmit data from the QDTC.

Converts the parallel transmit data into a serial data stream for the encoder/decoder (ED).

Maintains the inter-packet gap (IPG) for interframe spacing.

Generates and strips-off the 64-bit preamble.

Generates and checks CRC.

1-6

Determines transmit status.

Initiates retransmission on collision detect.

Performs address filtering to determine if this is the addressed node.

Converts the serial received data into parallel data for storage in the receive FIFO.

10.

Determines receive status.

1.2.4 Encoder/Decoder (ED)
The ED is implemented in high-speed logic, and is connected to the transceiver cable. It performs the
following physical layer functions.
1.

Encodes the serial transmit data stream from the EPP.

Transmits the Manchester-encoded data to the transceiver.

Decodes Manchester-encoded data received from the transceiver.

Sends the serial received data stream to the EPP.

Signals the EPP when it receives collision detect from the transceiver.

Performs the carrier sense function and signals the EPP when it detects the presence of a carrier
from the coaxial cable.

1.3 DEQNA SYSTEM OPERATION
The DEQNA and host communicate via two levels of data structures in host memory. First level
communication is via eight I/O page addresses in host memory space which correspond to 10 port registers
in the DEQNA. This level passes control and status, such as DEQNA error information (as opposed to
packet error status), interrupt enable, and DEQNA initialization. Second level communication, via the
host communications area, primarily comprises DMA transfers of transmit and receive data.
1.3.1 Port Registers
The DEQNA has 14 port registers, eight of which are in the DMARC. Ten of these registers are accessed
through the I/O page, as follows.
I.

Six read-only registers that are used to read the DEQNA's station address PROM.

Two 21-bit DMARC registers that hold the starting address of the transmit buffer descriptor
list and receive buffer descriptor list.

The 8-bit read/write DMARC register that holds the DEQNA's interrupt vector.

The 16-bit read/write DMARC register that is the DEQNA's Control and Status Register
(CSR).

1-7

The other port registers in the DMARC are not accessed via the I/O page.
1.

The transmit buffer address and receive buffer address are held in two 21-bit registers.

The transmit word count and receive word count are held in two la-bit registers.

A maximum of two DEQNAs can be connected to a host. A unique block of eight I/O page wordaddresses is assigned to each, for control and status transfers. (See Chapter 4, Paragraph 4.2.)
1.3.2 Host Communications Area
An initialized DEQNA has direct access to host memory. When set-up for a DEQNA, host memory has
space allocated for receive and transmit buffers and a data base. The data base comprises two sections: the
transmit buffer descriptor list, and the receive buffer descriptor list. (See Chapter 4, Paragraph 4.3.)
1.3.2.1 Buffer Descriptor List (BDL) - A descriptor describes a single buffer by its starting address and
length in words. (See Figure 1-6.) Transmit buffer descriptors include other parameters such as unaligned
first/last bytes, end of message indicator, and set-up mode flag. Every descriptor includes buffer status
and status of the packet that uses the buffer. Initial status is set by the software and updated by the
DEQNA.

STATUS WORD 2
FLAG

ADDRESS DESCRIPTOR BITS

H.O. ADDR BITS

LOW ORDER ADDRESS BITS

ONE
DESCRIPTOR

BUFFER LENGTH
OMIT IF [
CHAIN
ADDRESS

STATUS WORD 1
STATUS WORD 2
FLAG
MR·12439

Figure 1-6

BDL Format

Both buffer descriptor lists (BDLs) are forward-linked lists. The descriptors are either implicitly chained
(contiguous descriptors) or explicitly chained (with a chain address). If a list is explicitly chained at some
point, the address of the next descriptor (instead of the buffer starting address) is inserted into the current
descriptor and its chain address bit is set; buffer length and status words 1 and 2 are omitted.
1.3.3 Initialization
The DEQNA is reset during power-up by BUS INIT and can be reset by host software. At initialization,
the host writes the transmit BDL and receive BDL starting addresses to the DEQNA, validating the lists.
(See Chapter 4, Paragraph 4.2.4, CSR bits 04 and 05 descriptions.)

1-8

NOTE
The DEQNA will NOT respond to any commands
for approximately one second after power-up,
although the DEQNA will queue them.
1.3.3.1 Bootstrap - The DEQNA contains a 4-Kbyte ROM (BD ROM - Boot/Diagnostic ROM) that
host software can read. The BD ROM contains PDP-II code that is loaded into the host and executed as
an extension of the host's primary bootstrap code. (See Chapter 3, Paragraph 3.2.1.)
The BD ROM also contains minimum "good citizen" diagnostic code for the DEQNA. The DEQNA
relies on the host for Citizenship Test (CQ) assistance. When executed by the host, this code determines
that the DEQNA is a "good citizen" (that is, performing correctly) before it accesses the ETHERNET.
Three LEOs on the DEQNA are all turned on during DEQNA power-up initialization or when the host
fetches the boot/diagnostic code (for example, during reboot). The citizenship test turns off the LEDs, one
at a time.
1.
2.
3.

The first is turned off when the test starts running.
The second when internal loopbacks have successfully completed.
The third when external loop back has successfully completed.

Citizenship test completion leaves the DEQNA in internalloopback mode, preventing a faulty board from
generating spurious ETHERNET transmissions, and with all 14 target addresses set to the DEQNA's
physical address. (See Paragraph 1.3.4.1 and Chapter 3, Paragraph 3.2.2.)
1.3.3.2 Receiver Enable - Software can enable and disable reception in the EPP. The receive function is
initialized to the disabled state. Disabling the receive function does not affect a reception in progress; nor
does it affect set-up mode, externalloopback, or internal extended loopback.
1.3.3.3 Interrupt Vector - The Q-Bus interrupt controller chip in the QDTC uses the same interrupt
vector for transmit, receive, and Nonexistent Memory (NXM) interrupts. The vector assignment is
floating, and is written into a DMARC read/write register by software. (See Chapter 4, Paragraph 4.2.4,
CSR bits 02, 06, 07, and 15 descriptions.) Software must load the vector before enabling interrupts.
1.3.4 Loopback
There are four loopback modes: set-up mode, internalloopback, externalloopback, and internal extended
loopback. During set-up mode, internalloopback, and internal extended loopback, the transceiver cable's
transmit pair remains idle and the receive and collision pairs are ignored.
Receive status and transmit status are accumulated and stored during all four loopback modes. In internal
loopback mode, reception occurs after transmission is complete with transmit status stored. In the other
three modes, reception is in parallel with transmission; transmit status is not stored until reception is
complete and the receive status is stored.
Note that, with the exception of set-up mode, the loopback modes are exceptional operations, used only for
testing, and are not entirely performed in the same way as normal DEQNA operations.

1-9

1.3.4.1 Set-Up Mode - Set-up mode loads a set of 14 target addresses into the DEQNA's target address
RAM. The target address RAM is 128 bytes long, and is initialized by software at power-up. It holds 14
target addresses and 2 temporary copies of an incoming packet's destination address.
The target addresses are the node's physical address, the broadcast address,· and 12 multicast addresses.
The addresses are loaded from a transmit buffer in host memory (the buffer descriptor indicates set-up
mode). The frame is stored in the DEQNA instead of being transmitted. However, for verification and
synchronization, the information is looped through the receive logic and written into a receive buffer.
Control bits in the set-up mode buffer descriptor can expand the target addresses to include all multicast
packets or all packets (Promiscuous Mode). This allows a larger set of packets to be received, with
software filtering any unwanted destination addresses. (See Chapter 4, Paragraph 4.3.3.)
1.3.4.2 Internal Loopback (lLOOP) - The DEQNA is put in internalloopback mode by asserting (low)
CSR bit 08. In this mode, a 10-byte frame is transferred from a transmit buffer to a receive buffer
through a full-duplex internal loopback path. This mode exercises most of the DEQNA, and is the only
loopback mode that exercises all address recognition logic. The ILOOP packet comprises a 6-byte
destination address and a 4-byte CRC appended by the DEQNA.
Any ETHERNET activity concurrent with internalloopback mode is lost. The DEQNA is put in internal
loopback mode at initialization and software reset, preventing a failed DEQNA from transmitting on the
ETHERNET. (See Chapter 4, Paragraph 4.2.4, CSR bit 08 description.)
1.3.4.3 External Loopback (ELOOP) - This mode is entered by setting CSR bit 09. Normal packet
reception is disabled during operation in this mode. The ELOOP packet is of legal ETHERNET length
and is processed similarly to a normal packet. The packet is sent to the transceiver and transmitted on the
ETHERNET. The transceiver receive function senses the packet and loops it back to the DEQNA.
Address recognition logic is not checked, and the destination address is passed to the host, as usual.
If collisions occur on the ETHERNET while an external loop packet is being received, the Receive FIFO
is flushed.

Externalloopback mode is disabled at initialization and software reset. (See Chapter 4, Paragraph 4.2.4,
CSR bit 09 description.)
1.3.4.4 Internal Extended Loopback (IELOOP) - This mode is similar to external loopback, but the
packet is looped back internally instead of going to the transceiver. Internal extended loopback is entered
when CSR bits 08 and 09 are both asserted. The packet can be of any legal ETHERNET length~ or an
illegally long packet can be used to test the LONG receive status bit. Address recognition logic is not
checked, and the destination address is passed to the host, as usual.
Because CSR bit 09 is set (as it is in external loopback), normal packet reception is disabled during this
mode; and the mode is disabled at initialization and software reset (as is external loopback).
NOTE
The DEQNA CRC circuitry is full-duplex and is
checked in all loopback modes.

1-10

1.3.5 Sanity Timer
The sanity timer is enabled and reset by host software. After the timer is enabled, the software must
periodically reset it, otherwise it counts to its limit (that is, it times-out). If time-out occurs, the DEQNA
negates Q-Bus DCOK, causing the host power-up/power-down logic to initiate the host's primary bootstrap. Therefore, the timer monitors host software "sanity," triggering a system reboot if software
performance degrades to a point of DEQNA driver failure.
At initialization, the timer is disabled (or enabled, if a jumper is removed). The default time-out period is 4
minutes, and is software variable between 1/4 second and approximately 1 hour; the period reverts to 4
minutes following two successive time-outs. In response to a remote node request that it reboot itself, the
host can do so by allowing the time-out period to expire. (See Chapter 4, Paragraph 4.2.4, CSR bit 10
description, and Paragraph 4.3.3.2.)

1.3.6 Transmit
To initiate packet transmission, the host builds the transmit BDL and writes the BDL starting address into
the transmit descriptor address port register. The QDTC then updates the first descriptor's status to
USING (see Chapter 4, Paragraph 4.3.2), and continues by reading the buffer address, descriptor bits,
buffer length, and the buffer itself. If the buffer descriptor indicated that this buffer includes the end of
the message, the DEQNA attempts to transmit the packet. Otherwise, the message includes additional
buffers, and the QDTC updates the status of the additional descriptors, reading the necessary buffers until
the end-of-message is indicated, before attempting to transmit.
The QDTC reads the packet data (from one or more transmit buffers in host memory) into the EPP prefill
RAM. When it reads a descriptor with the end-of-message bit asserted and the last data has been
transferred from that buffer to the prefill RAM, the DEQNA attempts to transmit the packet stored in
the prefill RAM. If a collision occurs, the DEQNA attempts to retransmit the stored packet.
Transmit status is accumulated in the receive FIFO during and after successful or aborted packet
transmission. Eventually, the accumulated status is written into the two status words of the descriptor for
the last buffer of the packet, and the host is notified with an interrupt from the DEQNA.
The QDTC continues by accessing the next buffer descriptor. If the descriptor is valid, another transmission sequence begins. If the descriptor is not valid, the QDTC stops accessing the transmit BDDL and
associated buffers.
A valid buffer descriptor can also describe a chaining operation. Then, the descriptor chain address bit is
asserted, and the address in the descriptor points to another buffer descriptor instead of a buffer. (See
Chapter 4, Paragraph 4.3.2.3.)
The DEQNA transmit sequence is as follows.
1.

Write USING status into the buffer descriptor.

Read the buffer address and length from the buffer descriptor.

Start the buffer read on an odd byte (optional).

Read the packet from the buffer.

End the buffer read on an even byte (optional).

1-11

Either:
a.

Write USED status into the buffer descriptor and continue the transmission sequence
from the next buffer, or

start the transmission attempts with this buffer.

Write the transmit status into the buffer descriptor.

Interrupt the host at the end of the transmission sequence after writing the transmit status.

Either:
a.

Start the next transmission sequence from the next buffer, or

"chain" to the next BDL, or

invalidate this BDL.

1.3.7 Receive
Packet reception occurs in three states. First, the received packet's destination address field is compared to
the set of target addresses stored in the target address RAM. This address filtering occurs in parallel with
reception of the first 60 packet bytes. (Because the 4-byte CRC is stripped-off by the EDLC, these 60
bytes constitute a minimum valid reception.)
Second, if there is an address match and the packet is long enough, the packet continues to be stored in the
receive FIFO until the message is complete. However, if there is no address match or the packet is a runt
packet from a collision, the FIFO is either flushed or compensated. If the FIFO was previously empty, it is
flushed; but if the FIFO contained previous good data, it is compensated by setting RUNT in the received
status. Runt status is assigned to an incomplete packet stored in the receive FIFO because either address
match failed and the reception was truncated, or a collision occurred during reception and the packet was
too short.
Third, the QDTC empties the receive FIFO into the receive buffer(s) and writes the receive status into the
two status words of the final receive buffer descriptor. Multiple packets are queued in the receive FIFO as
they are received.
The DEQNA receive sequence is as follows.
1.

Write USING status into the buffer descriptor.

Read the buffer address and length from the buffer descriptor.

Write the received frame into the buffer.

Either:
a.

Write USED status into the buffer descriptor and continue the reception sequence into the
next buffer, or

end the reception sequence with this buffer.

1-12

Write the receive status into the buffer descriptor.

Interrupt the host at the end of the reception sequence after writing the receive status.

Either:
a.

Start the next reception sequence into the next buffer, or

"chain" to the next BDL, or

invalidate this BDL.

1.4 Q-BUS INTERFACE
The DEQNA works most efficiently with 22-bit block-mode memory. It also works with 18-bit memory
and non-block-mode memory. It relies on host software to map DMA addresses into the memory address
space.
The Q-Bus interface comprises slave and master logic.
1.4.1 Slave Logic
The slave logic gives the host access to the port registers in the DMARC and the station address PROM.
1.4.2 Master Logic
The master logic performs the QDTC DMA functions, including the following.
•
•
•
•
•
•

Addressing host memory
Transferring data
Fetching descriptors
Storing status
Incrementing addresses and word counts
Monitoring word count overflow

On systems with block mode memories, Q-Bus block mode DMA transfers give a data transfer rate of up
to 3.2 Mbytes/second. DMA transfers are automatically blocked at 4 to 16 words per bus acquisition.
The DEQNA includes a holdoff timer. This timer allows other DMA devices to acquire the bus, by
causing the DEQNA to wait for approximately 5 microseconds before re-requesting the bus (that is,
before reasserting BDMR). The timer is disabled if the receive FIFO is more than half full; for special
applications, it can be permanently disabled by adding a jumper.
The DEQNA also includes a bus time-out timer. This timer causes the bus cycle to abort and a
Nonexistent Memory (NXM) interrupt to be generated if the bus slave fails to respond within approximately 10 microseconds.
1.5 DEQNA SPECIFICATIONS
The DEQNA specifications are listed in Table 1.1.

1-13

Table 1-1

DEQNA Specifications

Specification

Description

Operating Mode

Half-duplex (non-loopback)

Data Format

Manchester encoded, serial

ETHERNET Data Rate

10 megabits per second

Q-Bus Backplane Loading

0.5 dc load
2.2 ac loads

DC Power Requirements (typical)
DEQNA
H4000 Transceiver

+5 V, 3.5 A
+12 V, 0.5 A

Operating Environment (System)
Temperature
Relative Humidity
Wet Bolt Temperature (maximum)
Dewpoint (minimum)
Altitude

5 to 50° C (41 to 122° F)
10% to 90%
28° C (82° F)
2° C (36° F)
Same as for system

Shipping Environment
Temperature
Relative Humidity
Altitude

Same as for system
Same as for system
Same as for system

In addition to those listed above, the DEQNA meets ETHERNET Specification, Version 2.0
requirements.
1.6 RELATED DOCUMENTS
Table 1-2 lists documents related to this guide.

Table 1-2

Related Documents

Title

Number

H4000 Ethernet Transceiver Field Maintenance Print Set

MP-01369

H4000 Ethernet Transceiver Technical Manual

EK-H4000-TM-PRE

The ETHERNET, A Local Area Network, Data Link
Layer and Physical Layer Specifications

AA-K759A-TK

Introduction to Local Area Networks

EB-22714-18

1-14

DIGIT AL personnel may order hardcopy documents from:
Digital Equipment Corporation
444 Whitney Street
Northboro, MA 01532
Attn:

Publishing and Circulation Services (NR03jW3)
Order Processing Section

Customers may order hardcopy documents from:
Digital Equipment Corporation
Peripherals and Supplies Group
P.O. Box CS2008
Nashua, NH 03061
For information on microfiche libraries, contact:
Digital Equipment Corporation
Micropublishing Group (BUOjE46)
12 Crosby Drive
Bedford, MA 01730

1-15

CHAPTER 2
INSTALLATION

This chapter describes the procedures to install a DEQNA in an LSI-II host system. The system described
is a MICRO/PDP-II system. The chapter includes the following sections.
Unpacking and Inspection - Verify that the shipment is complete and not damaged.
Preinstallation Verification - Verify that the host system meets the DEQNA installation
requirements.
Preparation - Prepare the host system and DEQNA for proper operation.
Installation - Install the DEQNA and transceiver cable in the host system.
Testing - Verify correct operation of the DEQNA and host system.
2.1 UNPACKING AND INSPECTION
Unpacking a DEQNA consists of removing the equipment from its shipping containers, verifying that no
parts are missing, and inspecting the equipment for damage. Report any damage or shortages to the
shipper and notify the Digital representative.

Before opening the shipping containers, look for external damage such as dents, holes, or
crushed corners.

Open and unpack each container. Inventory the contents using the shipping list. Table 2-1 lists
the parts supplied with each DEQNA.
NOTE
Shipping containers and packing materials should be
retained if reshipment is likely.

Inspect every DEQNA part for shipping damage. Check carefully for cracks, breaks, and loose
components.

2-1

Table 2-1

DEQNA Parts List

Part Description

Designation

DEQNA Module

M7504

Bulkhead Cable Assembly (one of the following):
53.3 cm (21 in) shielded cable/bulkhead (PDP-l 1/23)
30.5 cm (12 in) shielded cable/bulkhead (MICRO/PDP-II)
76.2 cm (30 in) shielded cable/bulkhead (PDP-II/23-PLUS)
3.048 m (10 ft) shielded cable (general use*)

CK-DEQNA-KA
CK-DEQNA-KB
CK-DEQNA-KC
CK-DEQNA-KD

DEQNA User's Guide

EK-DEQNA-UG-OOI

DEQNA PDP-II Diagnostic Set (Field
Diagnostic Resident Code)

CIQN DAO
AC-T6I2A-MC

* Non-FCC compliant installations

2.2 PREINSTALLATION VERIFICATION
To verify that the DEQNA can be correctly installed in the host system, the following requirements and
constraints must be met.
2.2.1 Host Boot/Diagnostic ROMs
Verify that the correct boot/diagnostic ROMs are installed in the host CPU. That is, the host CPU must
be capable of loading the extended bootstrap code from the DEQNA BD ROM.
2.2.2 Backplane Requirements
The DEQNA requires one dual LSI-II module slot configured for Q22-Bus (that is, extended LSI-II bus)
operation for highest performance.
2.2.3 Bus Latency Constraints
To get the best performance and avoid losing packets, the DEQNA should be the highest priority device
on the Q-Bus, that is, the DMA device nearest to the CPU. When two DEQNAs are installed, a blockmode memory is required, if high ETHERNET traffic rates are to be handled. The following is a
recommended module installation.
Processor
Memory
DEQNA I
DEQNA 2 / Other
Others

Slot I
Slot 2
Slot 3
Slot 4
Slots 5 - 8

2.2.4 Loading Requirements
Check that system loading capacity is not exceeded by installing the DEQNA. Table 2-2 shows the
DEQNA Q-Bus loading and Table 2-3 shows the DEQNA and transceiver power requirements.
CAUTION
Power supply voltages should be checked before and
after installation to verify the absence of overloading
and overvoltage conditions.

2-2

Table 2-2

DEQNA Q-Bus Loading

Module

Q-Bus dc Loads

Q-Bus ac Loads

M7504

0.5

2.2

Table 2-3

DEQNA Power Requirements

Voltage Rating
(Typical Values)

Typical
Current

Maximum
Current

Backplane
Pins

+5 ± 0.25 V @ 3.5 A

3.5 A

5.0 A

AA2, BA2. BVI

+ 12 ± 0.60 V @ 0.5 A
(for Transceiver)

0.5 A

BD2

Logic Reference

All, AMI, ATI,
AC2, BlI, BMI,
BC2

Transceiver Return

BTl

*At power-up or powered-up connect, transceiver surge current at the power connection is high enough to currentlimit and power-fail some power supplies. The DEQNA does not contain power supply surge protection; it must
be provided elsewhere if required by the system configuration.

2.3 PREPARATION
Prepare the host and DEQNA for installation using the following procedure.
2.3.1

Backplane
1.

Turn system power off, and unplug the ac power cord from the wall socket.
a.

Remove the rear plastic cover of the system unit by holding each end and pulling the cover
toward you. (Does not apply to rack-mounted units.)

Open the patch and filter panel assembly (also called the system I/O panel, the distribution panel, and the bulkhead). (See Figure 2-1.) Loosen the two screws at the end of the
panel opposite the hinge, and swing the panel open.

If necessary, reconfigure the system to accept the DEQNA in the appropriate backplane
slot. (See Paragraph 2.2.3.) Remove or relocate M7272 Grant Continuity cards as
necessary.

Plug the ac power cord into the wall socket, and turn system power on.

Measure the backplane voltages. They should be within the tolerances listed in Table 2-3.

Turn system power off and unplug the ac power cord from the wall socket.

2-3

UNUSED
OPTION PANELS

5O-PIN CONNECTOR
EXPANSION SLOTS
OR DEQNA PANEL
MA-12453

Figure 2-1

Patch and Filter Panel Assembly

2.3.2 M7504 Module
The DEQNA module, M7504, is configured with three jumpers, WI through W3, installed during
manufacture. (See Figure 2-2 and Table 2-4.) The disposition of these jumpers is described in the following
paragraphs.
2.3.2.1 Device Address Assignment (WI) - The DEQNA 110 page addresses are 17774440 (first
DEQNA) and 17774460 (second DEQNA). If two DEQNAs are to be installed, move jumper WI onto
the second DEQNA position, to set its 110 page address to 17774460. (See Chapter 4, Paragraph 4.2.)
2.3.2.2 Bus Request Holdoff Timer (W2) - Jumper W2 provides "fair" access to all DMA devices using
the Q-Bus (see Chapter 1, Paragraph 1.4.2), and should not be added, except for unusual requirements
(not supplied).
2.3.2.3 Sanity Timer (W3) - If not removed, jumper W3 disables the sanity timer at initialization. If
removed, jumper W3 enables the sanity timer at initialization. (See Chapter 1, Paragraph 1.3.6.)
2.3.3 Patch and Filter Panel Assembly
The transceiver cable bulkhead assembly will be installed in an unused option panel location on the system
110 panel. (See Figure 2-1.) Remove the option panel by removing the four screws. Save the screws.
2.4 INSTALLATION
Install and cable the DEQNA and the bulkhead assembly as follows. (See Figure 2-3.)
1.

Slide the M7504 module into the card guides with the component side nearest to the processor
module. Do not insert the module all the way into the slot at this time.

Insert the transceiver cable assembly into the system 110 panel with the four screws saved when
the blank panel was removed.

Connect the keyed cable of the bulkhead assembly to the module.

Slide the M7504 all the way into the card slot.

2-4

LEOs

TEST POINT 1

.. . I

~~~tr£"""~ ~ LWl

~.......".".. ~
BOOT/DIAG

STATION
ADDRESS
PROM

MA-12440

Figure 2-2

M7054 Showing Jumpers, LEDs, Transceiver Cable Connector,
Station Address PROM, and Boot/Diag PROM

Table 2-4

DEQNA Jumper Functions

Jumper

Function

Out/
2nd Position

WI
W2
W3

I/O Page Address
BDMR Holdoff Timer
Sanity Timer at Initialization

17774440
No Delay
Disabled

17774460
5 J,LS Delay
Enabled

2-5

2.5 TESTING
Perform the following tests to verify that the DEQNA and host system are operating correctly.
NOTE
In order to successfully run the citizenship (CQ)
diagnostic tests, either an operational ETHERNET
transceiver with cable must be connected to the
DEQNA 9 or the loopback connector must be connected to the bulkhead assembly.
2.5.1 Post-Installation Power Checks
Perform the following tests on the backplane slot that contains the M7504 module.
1.

Plug the ac power cord into the wall socket, and turn the system power on.

Measure the backplane voltages. They should be within the tolerances listed in Table 2-3.

Turn system power off.

2.5.2 Light-Emitting Diode (LED) Checks
The M7504 module includes three LEDs which indicate the operational status of the DEQNA. (See
Figure 2-2.) Table 2-5 defines the LED indications.

Table 2-5

DEQNA LED Indications

LED

Definition

OFF
OFF
OFF
ON

OFF
OFF
ON
ON

OFF
ON
ON
ON

The DEQNA passed all citizenship tests.
Transceiver, ETHERNET, or cable error.
DEQNA internal error.
Cannot upload BD ROM contents, the bootstrap has not yet executed, or
the first set-up packet pre fill has failed.

Connect either an ETHERNET transceiver with cable or a loopback connector to the transceiver cable connector on the patch and filter panel assembly. (See Figure 2-1.)

Turn system power on. All three LEDs on the M7504 module should be on within one second.

Boot the system from the DEQNA. Note that new CPU PROMs (with code for booting from
the DEQNA) must have been installed. The LEDs should be turned off, one at a time, until no
LEDs are on.

2-6

2.5.3

Diagnostic Acceptance Procedure
1.

Run the field functional test. (See Chapter 3, Paragraph 3.2.3.)

Turn system power off.

Close and fasten the patch and filter panel assembly.

If a loopback test transceiver was used, disconnect it.

Replace the rear plastic cover on the system unit. (Does not apply to rack-mounted units.)

If not already connected, connect the system to an installed ETHERNET transceiver.

Installation is now complete.

2-7

CHAPTER 3
SERVICE

This chapter describes servicing the DEQNA. It includes the following sections.
Maintenance Philosophy - Defines the DEQNA Field Replaceable Units (FRUs).
Diagnostics - Describes the DEQNA diagnostic programs.
Corrective Maintenance - Describes the corrective maintenance procedures for the DEQNA.
3.1 MAINTENANCE PHILOSOPHY
Corrective maintenance is performed by FRU replacement. The following are the field replaceable units.
1.
2.
3.
4.

M7504 module
Bulkhead cable assembly
Bulkhead fuse
Ampere filter (if used)
NOTE
When the module is replaced, the user may be able
to retain the original ETHERNET address by swapping the station address PROM from the replaced
module to the new module, and verifying with diagnostics that the original station address PROM
works in the new module.

3.2 DIAGNOSTICS
The DEQNA diagnostics include software to boot the DEQNA, tests to ensure that the module is working
correctly, and tests to isolate faults.
3.2.1 Extended Primary Bootstrap (EPB)
The DEQNA is loaded, or booted, in a way that is similar to mass storage device booting. Host primary
boot code passes control to the Extended Primary Bootstrap (EPB) code (loaded from the BD ROM),
which continues the bootstrap process by loading the complete contents of the BD ROM into host
memory. When the load is complete, the DEQNA citizenship test is run before the DEQNA is allowed to
access the ETHERNET.
If the citizenship test is passed, the bootstrap process continues. Control is transferred to either the
DECnet bootstrap, which is part of the Maintenance Operation Protocol (MOP) code loaded from the BD
ROM, or to an address in host memory.

3-1

If the DEQNA fails the citizenship test, the EPB code attempts to halt the CPU, without attempting to
boot DEC net or transferring control to a user's program. The LEDs on the DEQNA help to indicate the
nature of the failure.
In general, the boot sequence is as follows.
1.

Load the first 512 bytes of BD ROM. This is the EPB code.

Verify descriptor status and the CSR.

In the host, set up registers RO and Rl, and location 12 (octal) of main memory (see next step).
Continue.

If a failure is detected, examine location 12 (octal) of main memory. If location 12 is zero, halt
the EPB. If location 12 is non-zero, transfer control to the address contained in location 12.

Load the remaining bytes of the BD ROM into host memory.

Verify the BD ROM data transfer using the ROM checksum.

The host executes the citizenship test.

If the citizenship test fails, return control to the EPB and halt.

If the citizenship test passes, transfer control (as determined by the value in host register RO) to
either:
a.

The MOP code to boot DECnet. This code continuously attempts to boot DEC net until
successful or until stopped by the host.

User defined code.

3.2.2 Citizenship Test (CQ)
The DEQNA Citizenship Test (CQ) is a series of diagnostic test routines that determine if the DEQNA is
operating correctly and can access the ETHERNET or is faulty and requires further diagnosis. Test
results are indicated by the LEDs on the DEQNA and are returned in host register RO, where they are
accessible to software. The CQ test uses internal loopback, internal extended loopback, and external
loopback modes, and requires the DEQNA and an H4000 transceiver (or equivalent); connection to the
ETHERNET is not required. Prior to executing the tests, CQ turns off the sanity timer. Upon completion
of the tests, it turns the sanity timer on if jumper W3 is removed (timer enabled), or leaves the timer off if
jumper W3 is in place (timer disabled).
The CQ test is a free-standing subroutine and can be called by other software. For example, during
network boot, CQ can determine if the node should be allowed to proceed from the initialized state to
either a functional state or nonfunctional state. If a fault exists, MOP code can call CQ to determine if
other DEQNA diagnostics or network-level diagnostics are required for fault isolation.
3.2.2.1 Test Descriptions - The tests are described in the following list. Corresponding bit numbers in
host register RO are given for each possible error reported by the test. An error summary is given in
Paragraph 3.2.2.2.

3-2

Station Address Verification - The default physical address is verified and copied from the
station address ROM into a test packet for later use. If this test fails, testing continues until the
final external loopback test or another test failure occurs. Possible errors are:
RO Bit

Description

00
00
00

Station address is all zero bits.
Station address is all one bits.
Station address is not a valid DEQNA address.
Bus time-out or nonexistent memory error.

10
2.

Device Interrupt and Nonexistent Memory - After interrupts are enabled, a transmit buffer
descriptor chained to a nonexistent memory location is sent to the Unit Under Test (UUT), that
is, one of the two possible DEQNAs. The UUT should generate a transmit interrupt with the
CSR NI bit (bit 02) set. Possible errors are:
RO Bit

Description

11
11
11

No interrupt occurred.
Interrupt occurred prematurely.
Wrong interrupt occurred.

Set-up Mode and Receive FIFO Processing - A series of set-up packets is transmitted to the
UUT, to test "stuck-at" faults. The packets contain repeating test patterns which are varied to
test each target address RAM byte with all patterns. The set-up packets are echoed into the
receive FIFO and verified. The set-up packet lengths are such that all the receive FIFO bytes
receive each of the four basic patterns, as the operation is repeated. Possible errors are:
RO Bit

Description

12,01
09,12,01
14,12,01

Target address echoed data check.
Set-up packet operation time-out.
Set-up packet operation status check.

Internal Loopback and Address Filter - A target address set-up packet with "walking" bit
pattern is generated and set-up in the UUT. Then, two internalloopback packets are generated
and transmitted for each address in the pattern. The first packet is addressed to the complemented target address (not in the pattern), and must be correctly transmitted and received as a
runt. (See Chapter 1, Paragraph 1.3.7.) The second packet is addressed to a target address in
the pattern, and must be correctly transmitted and received.
The test is repeated with the walking bit = 1 and the walking bit = 0. Possible errors are:

RO Bit

Description

02
09,02
09,02
12,02
14,02
14,02
09,12,02
14,12,02

Transmitted and received and data compare check.
Runt packet transmit and receive operation time-out.
Valid packet transmit and receive operation time-out.
Target address echoed data check.
Runt packet transmit and receive operation status check.
Valid packet transmit and receive operation status check.
Set-up packet operation time-out.
Set-up packet operation status check.

3-3

Internal Extended Loopback and Protocol - The UUT is put in internal extended loopback
mode and packets of increasing length are circulated through the transmit buffer (prefill RAM)
and the receive FIFO. The packet bit patterns are intended to uncover "stuck-at" conditions
and faults in buffer and FIFO processing. The received packets are verified to be sure that data
was correctly transferred. The packet lengths increase in 3-byte increments, from the minimum
ETHERNET packet size to beyond the maximum size. The test completes when the UUT
detects the expected long packet. Possible errors are:
RO Bit

Description

03
03
09,03
14,03

Long packet not detected via device transmit status.
Internal extended loopback transmit/receive data compare check.
Test packet transmit or receive operation timed-out.
General operation status, check, long packet not detected.

DMA Q-Bus Interface Processing - An internal extended loopback packet based on a transmit
BDL with contiguous and chained unaligned buffer segments is transmitted using the default
physical address. This packet is received and verified. Possible errors are:
RO Bit

Description

04
09,04
14,04

DMA Q-Bus interface transmit (scatter/gather) data check.
Transmit (special) and receive operation time-out.
Receive or transmit operation status check.

Transceiver Operational and Status - A set-up packet with the physical address of the UUT is
generated and sent to the target address RAM. The packet also turns off LED 2. The CSR
carrier bit (bit 13) is monitored to be sure it is cleared; or, if it is set, that it is cleared within
approximately 100 microseconds. Possible errors are:
RO Bit

Description

12
09,12
14,12
15

Target address packet with LED command echoed data check.
Set-up packet operation time-out.
Set-up packet operation status check.
CSR carrier bit on too long.

External Loopback and ETHERNET Protocol - This test is executed only if no other errors
have been detected.
The physical address of the UUT is assumed to be in the target address RAM. A minimum size
ETHERNET packet, with a descending-integers data pattern and addressed to the UUT, is
transmitted and received using externalloopback. Next, a maximum size ETHERNET packet
with the same characteristics is generated and sent to the UUT. Both packets test ETHERNET
protocol processing, and the maximum size packet also tests the transmit buffer.

3-4

Packets which "go on the wire" are compatible with loopback test packets, have the protocol
type set to loopback, and other fields set such that testers ignore these packets. The destination
(and source) address of the loopback packet is the assigned ETHERNET station address of the
UUT (that is, its default physical address). Possible errors are:
RO Bit

Description

15
05
09,05
14,05

Externalloopback over ETHERNET cable is not operational.
Minimum or maximum sized packet data compare check.
Minimum/maximum packet operation time-out.
Minimum/maximum packet operation status check.

3.2.2.2 Test Results - The CQ test will either execute successfully or fail. The two possibilities are
described below.

If the CQ test executes successfully, the value of host register RO is zero and the DEQNA is setup as follows.
a.

All three LEDs are off.

All 14 target addresses are set to the physical address from the station address ROM.

The sanity timer is set to its default interval (4 minutes) and disabled or enabled, according
to the disposition of the sanity timer jumper (W3).

Promiscuous and all multicast address modes are off.

The DEQNA has been reset:
Receive is disabled
Transmit is disabled

If the CQ test fails, the LED indications will display the following error codes.
LED
1

Definition

OFF
OFF
ON

OFF
ON
ON

ON
ON
ON

Transceiver or ETHERNET error
DEQNA internal error
Cannot upload BD ROM contents or the first set-up packet
prefill failed.

If the DEQNA passed the tests, all the LEDs are off.

3-5

The bits in register RO indicate the test that failed. If bit 15 is the only bit set, the DEQNA passed all the
CQ tests except those which require a connected transceiver. The errors/bits are defined as follows
(multiple bits can be set).
Error/
Bit

Error Definition and Source(s)

External loopback not operational (Tests 7 and 8)
ETHERNET not operational
H4000 not operational (blown fuse, disconnected)

Operation completion status check (all tests)
CSR status after final reset not nominal
CSR status after transmit and/or receive not nominal
Receive descriptor flags and status word 1 not nominal
Received byte length check
Transmit descriptor flags and status word 1 not nominal
TDR value = 0

Sanity timer interrupt (general error)
Power failed during test
Unexpected sanity timer interrupt

Set-up packet or target address echo check (all tests)
Set-up packet transmit time-out
Transmit status not nominal
Set-up packet receive time-out
Receive status not nominal
Echoed data not identical to transmitted data
Extra word at end of set-up packet not nominal

Spurious or missing device interrupt (general error)
Expected device interrupt not detected
Device did not detect nonexistent memory (NXM) bus state
18-bit or 22-bit addressing failure
Unexpected DEQNA device interrupt

Bus time-out or NXM interrupt (general error)
I/O page not accessible for read or write
Cannot read station address ROM
Test code attempted to access nonexistent memory

Device operation time-out (all tests)
Unit under test failed to complete a transmit and/or receive in time

Undefined

3-6

Undefined

ETHERNET externalloopback test check (Test 8)
ETHERNET protocol processing check
ETHERNET minimum valid length processing check
ETHERNET maximum valid length processing check
DMA interface processing check (Test 6)

DMA odd/even length and address processing check
Multielement transmit descriptor processing check
Chained transmit descriptor processing check
Internal extended loopback transmit buffer data check (Test 5)

ETHERNET protocol processing check
Transmit buffer memory malfunction
Packet size processing error (protocol error)
Station address compare test check (Test 4)

Address filter logic passing all addresses
Address filter logic not passing expected addresses
Station address/receive FIFO processing check (Test 3)

Target address RAM malfunction
Packets not properly stored in receive FIFO
Receive FIFO memory malfunction

Invalid ETHERNET station address (Test 1)
I/O page register read failure (see also bit 10)
Unit under test is not a DEQNA (M7504)
Station address ROM malfunction
Invalid DEQNA address

3.2.3 Field Functional Test
The Field Functional Diagnostic Program (ZQNA) tests the DEQNA in Q18 or Q22-Bus systems. It
attempts to isolate faults to the following FRUs.
1.
2.
3.
4.
5.

DEQNA
Bulkhead assembly
Bulkhead assembly fuse
Transceiver cable
Transceiver

3-7

The ZQNA also attempts to localize faults to the failing DEQNA functional area(s).
1.
2.
3.
4.

Q-Bus DMA Transfer Controller (QDTC)
Receive First-In/First-Out (FIFO) and transmit buffer memory
ETHERNET Protocol Processor (EPP)
Manchester Encoder/Decoder (ED/DE)

Tests are executed under the supervision of the XXDP/DRS, and controlled by an operator from a console
(hard copy or video). For DRS commands, see Appendix C, Paragraph C.4, or the XXDP+ User's
Manual.
Note that the ZQNA diagnostic program is not an ETHERNET network exerciser. The ZQNA assures
that the module can execute ETHERNET protocol and that valid network traffic can be transmitted and
that valid network traffic can be received. The network exerciser (see Appendix C) provides a higher level
of testing.
3.2.3.1 Configuration and Set-Up - The DEQNA is tested in allioopback modes. The ZQNA tests the
DEQNA in internalloopback and internal extended loopback modes, with or without an externalloopback
connector or transceiver connected (that is, a connected transceiver or the'loopback connector does not
have to be unplugged). Externalloopback mode is used with a connected transceiver or externalloopback
connector. Executing ZQNA using external loopback mode in a system connected to a "live"
ETHERNET does not disrupt the ETHERNET. Alternatively, externalloopback mode can be used with
a terminated transceiver that is not attached to a network cable.
The functional areas tested in each loopback mode are shown in Table 3-l.
Table 3-1

ZQNA Tested Functional Areas
Loopback Mode

Functional Area *

Setup

Internal

Internal
Extended

External

Q-Bus

QDTC

FIFO

ED/DE

EPP

EPP Address
Checking Logic

Transcei ver
and Cables
*Q-Bus
QDTC
FIFO
EPP
ED/DE

X
Processor data bus
Q-Bus DMA transfer controller
= Transmit and receive memory buffers
= Ethernet protocol processor
= Manchester encoder/decoder
=
=

3-8

The sanity timer jumper (W3) must be removed to enable the timer before executing the sanity timer test
(described in item 21 of the following paragraph). When sanity timer testing is complete, the jumper
should be restored to its position before the test.
3.2.3.2 Test Descriptions 1.

Nonexistent I/O Page Register Test - This test verifies that all the device registers residing in
the I/O page can be accessed without forcing a nonexistent memory (NXM) interrupt.
Hardware Tested: Q-Bus to DEQNA port register interface.

CSR Bit Test - This test verifies that the CSR register static bits can be set and cleared as
specified. The host writes data patterns to the CSR and reads them back, checking for static
(stuck at 1 or 0) faults.
Hardware Tested: Q-Bus to DEQNA port register interface.

ETHERNET Station Address Verify Test - This test verifies that the ETHERNET station
address PROM can be correctly read and loaded to host memory. The ETHERNET station
address is read from the PROM and a checksum is computed; this checksum is then compared
to the checksum stored in the PROM. The ETHERNET station address is always printed out
on the console in the ETHERNET standard format. If the address is not correct, the error is
recorded and an appropriate error message is printed out on the console.
Hardware Tested: Station address PROM and Q-Bus to DEQNA port register interface.

Interrupt Vector Address Test - This test verifies that all bits of the vector address register can
be set and cleared as specified. The host writes data patterns to the register and reads them
back, checking for static (stuck at 1 or 0) faults. Note that only bits <09:02> of the interrupt
vector address register are valid; the rest are read as zero.
Hardware Tested: DEQNA vector address register and port registers.

Boot/Diagnostic ROM Checksum Test - This test verifies that the contents of the BD ROM
can be correctly loaded into host memory. The ROM data is read and a checksum computed;
this checksum is then compared to the checksum stored in the last word location of the BD
ROM.
Hardware Tested: Q-Bus DMA interface, 8051 microprocessor, 8051 ROM, CSR, and receive
FIFO.

Interrupt Sanity Test - This test verifies that the DEQNA interrupts the processor at only the
expected level (4), not any other level.
Hardware Tested: Q-Bus QDIC interface, CSR, Q-Bus time-out logic, and QDTC interrupt
logic.

ETHERNET Carrier Sense Test - This test verifies that the DEQNA can transmit loopback
packets. The DEQNA must be connected to the transceiver to run this test successfully.
Hardware Tested: Carrier sense circuitry and ED/DE chip.

3-9

Station Address RAM Test - This test verifies that the station address RAM has no static
faults. The host writes and then reads data patterns to all of the addressable RAM (572 bytes).
Write and read data patterns are compared to check for errors. The test continues until all the
data patterns are exhausted.
Hardware Tested: Station address RAM, Q-Bus QTDC interface, CSR bit 00 (Receiver
Enable), and part of receive and transmit FIFO.

Promiscuous Station Address Test - This test verifies that DEQNA promiscuous addressing
mode functions as specified. The test uses bit patterns and addresses within and out of the set-up
address range, to assure that there is true promiscuity.
Hardware Tested: Promiscuous addressing mode logic.

10.

Transmit and Receive FIFO Memory Test - This test verifies that link memory (receive FIFO
and transmit buffer) has no static faults. The host writes and then reads a sequence of data
patterns to all of the link memory. The received pattern is compared to the transmitted pattern
to check for errors. The test continues until all the data patterns are exhausted.
Hardware Tested: Transmit buffer address logic, transmit buffer memory, receive FIFO
address logic, and receive FIFO memory.

11.

Packet Length Test - This test verifies that DEQNA can transmit and receive variable length
packets (equal to or greater than 60 bytes and equal to or less than 1514 bytes without the
CRC) without losing any data in the process. This test also verifies that the ninth bit of the
FIFO memory is not static (stuck at 1 or 0).
Hardware Tested: Transmit and receive RAM.

12.

Descriptor List Address and Interrupt Test - This test verifies that transmit and receive list
invalid bits (CSR bits 04 and 05) can be set and reset as specified; and that both transmit and
receive descriptor list addresses in the I/O page have to be valid to successfully loopback a
packet.
Hardware Tested: Q-Bus to QTDC interface - valid and invalid host memory address processing; CSR register bits 02 (NXM Interrupt), 06 (Interrupt Enable), and 05 (Receive List
Invalid).

13.

Buffer Address and Interrupt Test - This test verifies that the buffer address in the descriptor
list has to be valid in order to loopback a packet. A nonexistent memory interrupt is generated if
an invalid buffer address is specified in the descriptor list.
Hardware Tested: Q-Bus to QTDC interface - valid and invalid host memory address processing; CSR register bits 02 (NXM Interrupt) and 06 (Interrupt Enable).

14.

DMA Timing Test - This test uses a chained loopback packet, to verify that the DMA transfer
completes within "n" milliseconds. The number of milliseconds, "n," depends on the operator's
response to the prompt:
SYSTEM HAS BLOCK MODE MEMORY (L)?

3-10

Hardware Tested: Internal extended loopback, transmit status - last descriptor in chain (bit 15),
and receive status - last descriptor in chain (bit 15), and error summary (bit 14).
15.

Long Packet Test - This test verifies that DEQNA can detect long packets (1600 bytes or
more, with the CRC) when transmitted in internal extended loopback mode.

Hardware Tested: Receive status - error summary (long packet - bit 14).
16.

Odd Packet Test - This test uses chained and unchained descriptor lists to verify that the
DEQNA can transmit and receive packets of odd length, and packets that start and/or end on
odd addresses.

Hardware Tested: CSR bits 04 (Transmit List Invalid) and 05 (Receive List Innvalid), and
transmit descriptor bits (transmit buffer ends on odd byte and transmit buffer ends on even
byte).
17.

Station Address Test - This test verifies that DEQNA accepts only packets with legitimate
multicast and nonmulticast addresses, and discards those with illegitimate multicast and
non multicast addresses.

Hardware Tested: Address filter circuitry.
18.

All Multicast Station Address Test - This test verifies that the DEQNA recognizes the allmulticast addresses of the node and discards loopback packets with nonenabled addresses.

Hardware Tested: All-multicast addressing, 8051 microprocessor, and address filter circuitry.
19.

Runt Packet Test - This test verifies that the DEQNA can detect runt packets in FIFO.

Hardware Tested: EPP, address filter circuitry.
20.

FIFO Overflow Test - This test verifies that the ETHERNET protocol processor can detect a
receive FIFO overflow condition.

Hardware Tested: Receive status word 1, bits 14 (Error), 12 (Discard), and 00 (Overflow); and
EDLC byte FIFO.
21.

Sanity Timer Test - This test verifies that the sanity timer times out after a pre-set time-out
period (supplied by the operator).
-

Hardware Tested: Sanity timer logic.

3-11

3.2.3.3 Operation - Tests are executed under the supervision of the XXDP /DRS. For DRS commands
see Appendix C, Paragraph C.4, or the XXDP+ User's Manual. ZQNA - specific prompts and responses
can be divided into three categories: start-up procedure (XXDP+), hardware questions, and software
questions. These are described below.
Start-Up Procedure (XXDP+) - To start-up this program, use the following procedure.

Boot XXDP+

Give the date

Type: R NAME (where NAME is the name of the BIN file for this program)

Type: START

Type: Y (yes) in response to the CHANGE HW prompt

Answer all the hardware questions

Type: Y (yes) in response to the CHANGE SW prompt

Answer all the software questions

This procedure uses only the defaults for flags and software parameters.
Hardware Questions - When a diagnostic is started, the DRS requests hardware information with the
prompt:
CHANGE HW (L) ?
Y (yes) is the correct response after a START command, unless hardware information has been preloaded
using the Set-up Utility. (See the XXDP+ User's Manual, Chapter 6.) When it receives a Y response, the
DRS requests the number of units. It then requests the following information for each unit.

# OF DEVICES (D) ?
The response is the number of units to be tested (no default). This response determines the number of
times the following information is requested. One device must be specified.
DEQNA I/O PAGE ADR (0) 174440?
The response is the address of the I/O page register assigned for one of the DEQNA devices. The legal
I/O page addresses are 174440 and 174460.
INTERRUPT VECTOR ADR (0) 700 ?
The response is the DEQNA interrupt vector address. The interrupt vector address is 700 (octal) for the
DEQNA at I/O page address 174440, and 704 (octal) for the DEQNA at I/O page address 174460.
Software Questions - After the hardware questions are answered, or following a RESTART or CONTINUE command, the DRS requests software parameters. These parameters govern some diagnostic-specific
operation modes. The prompt is:
CHANGE SW (L) ?

3-12

The response is Y (yes) to change any parameters. Three software questions follow. The first question is:
DO YOU WANT TO TEST SANITY TIMER (L)?

If the response is Y (yes), the DRS displays two additional prompts:
IS SANITY TIMER JUMPER ENABLED/CUT (L)?
The response is Y (yes) if the sanity timer jumper is removed; otherwise remove the jumper and then
type Y.
SANITY TIMER TIMEOUT VALUE (O)?
The response is a decimal time-out value (between 0 and 7) that represents the time-out period,
according to Table 3-2.
The second question is:
EXECUTE TESTS IN INTERNAL/EXTENDED LOOPBACK MODE (L)?
A Y (yes) response causes test to execute in internal and internal extended loopback modes. A N (no)
response causes tests to execute in internal and external loopback modes.
The third question is:
SYSTEM HAS BLOCK-MODE MEMORY (L)?
The response is Y (yes) if the system has block-mode memory and N if it has non-block-mode memory.

Table 3-2

Sanity Timer Time-Out Values

Time-Out
Value

Time-Out
Period

1/4 second
1 second
4 seconds
16 seconds
1 minute
4 minutes
16 minutes
64 minutes

2
3
4
5
6
7

3-13

3.2.3.4 Error Reporting - A diagnostic can issue general and specific types of error messages.
General error messages are always printed unless the IBE and/or IER flag is set, and have the format
shown in Figure 3-1.

MR-12B03

Figure 3-1

General Error Message Format

where:
NAME
Diagnostic name
ER--TYPE= Error type (all errors are hard errors)
ER--NO
Error number
UNIT_NO= 0
TEST_NO= Test and sub test where error occurred
PC--ADDR= Program counter contents
General error messages may include two sublevels: basic error messages and extended error messages.
Basic error messages are printed after the associated general error message, and contain some additional
information about the error. They are always printed unless one or more DRS error flags (IBE, IXE, IER)
are set.
Extended error messages are printed after the associated general error message and any associated basic
error messages. Extended error messages contain additional error information, such as register contents or
good/bad data. They are always printed unless either the IXE or IER flag (or both) is set. The format of a
typical extended error message is shown in Figure 3-2.

TRANSMIT DESCRIPTOR LIST

RECEIVE DESCRIPTOR LIST

FLAG WORD
LOW-ORDER ADDRESS BITS
HIGH-ORDER ADDRESS BITS
PACKET LENGTH (BYTE)
STATUS WORD 1
STATUS WORD 2

FLAG WORD
LOW-ORDER ADDRESS BITS
HIGH-ORDER ADDRESS BITS
PACKET LENGTH (BYTE)
STATUS WORD 1
STATUS WORD 2
MR-12B04

Figure 3-2

Typical Extended Error Message Format

3-14

Specific error messages will be defined as needed. The following are possible error messages.
Device fatal error messages:
CSR REGISTER FAILED TO RESPOND
NO INTERRUPT FROM DEQNA
Return status messages.
TRANSMIT STATUS ERROR
RECEIVE STATUS ERROR
CSR STATUS ERROR
3.2.4 DEQNA DEC/XII Exerciser
The DEQNA DEC/XII Exerciser, also called the QNA Option Module (QNA OPMOD), exercises one
DEQNA at maximum activity rates in order to provoke noise, timing, and logical interaction failures. It
transmits and receives random length packets (using either 18- or 22-bit physical address space). The
DEQNA transmits and receives the same packet.
One pass of the exerciser consists of 1000 iterations of transmitting a packet, receiving a packet, and
comparing the contents of the transmit packet to the receive packet. Packet length is random for each
iteration. Transmit and receive status words and CSR status are all checked for correct contents.
The DEQNA is dropped from further testing if any of the following occurs.
1.
2.
3.
4.
5.

The DEQNA does not reset properly.
The CSR and/or the receive and/or transmit status word(s) are in error.
A hard error occurs. A transmit and/or receive interrupt is not generated.
The transceiver is disconnected while in external loopback mode.

Internal extended loopback mode is the default mode of operation.
3.2.4.1 Configuration and Set-Up - It is assumed that, prior to running this exerciser, both the DEQNA
citizenship test and field functional test have been successfully run. The default parameters are:
Device address: 17774440
Interrupt Vector: 700
BR level: 5
Number of devices: 1
The holdoff timer jumper (W2) must be removed and the sanity timer jumper (W3) must be in place
(both as shipped).
To run the exerciser in externalloopback, the DEQNA under test must be connected to the transceiver or
the externalloopback connector must be connected.
Software Register 1 (SRI) bit 0 and 1 options are described in Table 3-3.

3-15

Table 3-3

DEQNA DEC/XII Exerciser Software Register Bits

Bit

Value

Description

Exerciser runs in internal extended loopback mode (default). Transceiver is not
needed.

Exerciser runs in external loopback mode. Transceiver or external loopback connector is required.

Print error messages.
Do not print error messages.

3.2.4.2 Commands - To set externalloopback mode, type the following commands.
MDD QNAAO 16<RETURN>
1<RETURN>
To test a DEQNA in the second slot (address 17774460), type the following commands after the exerciser
has been loaded.
MOD QNAAO 6<RETURN>
174460<LINE FEED>
704<RETURN>
For additional information refer to the DEC/X]] User's Manual, CWQUACO.
3.2.4.3 Error Messages - Error messages print the contents of the DEQNA descriptor lists in the order
shown in Figure 3-3,
DEONA -

"ERROR MESSAGE"

TRANSMIT DESCRIPTOR LIST

RECEIVE DESCRIPTOR LIST

FLAG WORD
LOW-ORDER ADDRESS BITS
HIGH-ORDER ADDRESS BITS
PACKET LENGTH
STATUS WORD 1
STATUS WORD 2

DEONA CSR REGISTER
DEONA I/O PAGE ADDRESS
MA-12805

Figure 3-3

DEQNA DEC/XII Exerciser Error Message Format

where "error message" is one of the following.
DEQNA WILL NOT RESET
DEQNA - BAD DEQNA STATUS
DEQNA - BAD RECEIVE STATUS

3-16

DEQNA - BAD TRANSMIT STATUS
DEQNA - XMIT PACKET LENGTH NOT = RCV PACKET LENGTH
DEQNA - ATTEMPT TO ACCESS NONEXISTENT MEMORY LOC
Note that transmit and receive descriptor lists are not printed with a DEQNA WILL NOT RESET error
message.
3.3 CORRECTIVE MAINTENANCE
Replace the failed FRU (see Paragraph 3.1) as indicated by the error code returned by the citizenship test
in RO or the error indicated by the field functional test.

3-17

CHAPTER 4
PROGRAMMING·

This chapter contains the information needed to program the DEQNA-KP. It includes detailed descriptions of the formats and functions of the port registers and Buffer Descriptor Lists (BDLs).
4.1 OVERVIEW
The DEQNA and host communicate on two levels. First level communications, via I/O page access of
port registers, are DEQNA control and status transfers, such as:
1.
2.
3.

DEQNA initialization
buffer descriptor pointers (that is, starting addresses)
DEQNA error status (as opposed to packet error status).

Second level communications, via the transmit BDL and receive BDL, are DMA transfers between the
DEQNA and transmit and receive descriptors and data buffers in host memory.
4.2 CONTROL AND STATUS TRANSFERS
Each DEQNA is assigned a block of eight I/O page locations (words), used as registers, and available for
user programming. The blocks are allocated at I/O page locations 17774440-17774456 and
17774460-17774476 (two DEQNAs are allowed). See Figure 4-1. Six locations (read-only) are used to
read the station address PROM. Four locations (write-only) pass the high and low order transmit BDL and
receive BDL starting addresses. Note that these same four locations are used in read-only mode as part of
the six locations that are used to read the station address PROM (that is, these four locations overlap the
previous six read-only locations). The next register (read/write) stores the DEQNA's interrupt vector. The
final register (read/write) is the DEQNA's control and status register (CSR). All the registers are wordaddressable only. A detailed description follows.

4-1

STATION ADDRESS PROM (RO)

----r-:--'--"""""'--'---'----'r---T'":-----r-:-.-~--r---1140
08

177744

r---r-~~I--,.~

(60)

~~__~__~I_R_ES_E~~_V_ED~__~__~__~__~__~__~.__~.__~__~__~~ ~~~~~~H
RECEIVE SDL START ADDRESS (WO)

15:00
21:16

•

MIMI
46 (66)

I ·

TRANSMIT SDL START ADDRESS (WO)

15:00

~•

21:16

1501701

52 (72)

I ·

VECTOR ADDRESS (R/W)

00
RR

54 (74)

CSR (R/W)

RR--,-I_C_A~_O_K~_R_R---,-_S_E

L.I_R_I...JI__

E~I_R_L--L.I_X_L_IL...-S_D--L...._N_I

--L...._E_L--L...._IL--LI_XI--,-__
I

RR = RESERVED

....II__
S R----L__
RE--I156 1761

MR-12441

Figure 4-1

Port Registers

4.2.1 Station Address Registers
The station address PROM is read via the lower byte of these six locations. The PROM holds the 6-byte
default ETHERNET physical address of the DEQNA, as well as a 2-byte checksum on the 6-byte
address. The checksum bytes are read in reverse order from the first two locations, after setting CSR bit
09. See Paragraph 4.2.4, CSR bit 03.)
4.2.2 BDL Starting Address Registers
The two transmit and two receive BDL starting address registers point the DEQNA to the start of the
appropriate buffer descriptor list. (See Paragraph 4.3.2.2.) The registers are write only and must be
written with word instructions. And, the low-order address bits must be written before the high-order
address bits; for example, to set-up the transmit list, register 17774450 is written before register
17774452. The DEQNA then starts its functions.
When it gets a receive list address, the DEQNA fetches a buffer descriptor from the receive BDL and
starts a DMA transfer from the receive FIFO to the receive buffers, transferring any packets that the EPP

4-2

has passed to the receive FIFO. When it gets a valid transmit list address (and if the DEQNA is not busy
with a reception), the QDTC fetches a buffer descriptor from the transmit BDL and begins a DMA
transfer from the transmit buffers to the prefill buffer.
A current list address must be invalidated before a new list address is loaded; if not, the results are
unpredictable. (List invalidation is described below.)
4.2.3 Vector Address Register
The vector address read/write register holds the DEQNA's interrupt vector address. The vector address is
assigned floating with a priority rank of 47. It is configured at system start-up using the floating vector
autoconfiguration routines. If the system is being bootstrapped via the DEQNA and is running the
DEQNA self-test code, the vector address is temporarily assigned to location 774 (octal), the standard
diagnostic vector. The register bit definitions are as follows.
Bit

Definition

15: 10

rr - Reserved. Read as zero.

09:02

Interrupt Vector Address. Read/write. When the register is read, the value in these bits is
such that bits 15:00 are the address of the vector to the DEQNA's interrupt service routine.

01 :00

rr - Reserved. Read as zero.

4.2.4 Control and Status Register (CSR)
The primary functions of the CSR are to control the DEQNA's operating mode and report its status. The
CSR bit definitions are as follows.
Bit

Definition

RI - Receive Interrupt Request. Read/write 1. The DEQNA sets this bit when it has
received a packet, transferred the packet to the receive buffers, and updated the receive
buffers' status in the last buffer's descriptor. The interrupt service routine must clear this bit
(write 1 to clear, write 0 has no effect) to allow subsequent interrupt requests (also see bit
06).
This bit is cleared by power-up initialization and software reset.
NOTE
Interrupts are not queued. If the DEQNA processes
multiple messages before the interrupt request bit is
cleared, additional interrupts are not requested.

rr - Reserved. Not usable.

CA - Carrier. Read only. This bit reflects the status of the ED's Carrier Sense signal. It can
be polled to determine the amount of ETHERNET activity, except when the DEQNA is in
an internal loopback mode or the transceiver is disconnected.

OK - Fuse OK. Read only. When set, this bit indicates that the fuse on the transceiver cable
bulkhead is supplying voltage. When cleared, this bit indicates the fuse is blown or there is
no power to the bulkhead.

rr - Reserved. Not usable.

4-3

SE - Sanity Timer Enable. Read/write. When set and sampled, this bit allows the sanity
timer to count to its limit (that is, time-out). When cleared and sampled, this bit both clears
and disables the sanity timer. The bit is sampled only after a set-up mode packet of 128 to
255 bytes. (See Paragraphs 4.3.3.2 and 4.3.3.3.)
If the timer is enabled, all transmissions (normal, loopback, or set-up) reset the timer and
leave it enabled. If the count reaches its limit, Q-Bus DCOK is negated for approximately
7.2 microseconds, causing the host to reboot itself.

The timer is cleared and disabled at power-up if the timer jumper (W3) is in place. If the
timer jumper is removed, the timer is enabled at power-up. The default time-out period is 4
minutes but can be varied. (Se~ Paragraph 4.3.3.2.)
09

EL - External Loopback. Read/write. When set, this bit puts the DEQNA into external
loopback (ELOOP) mode. Asserting both this bit and ILOOP (bit 08) puts the DEQNA
into internal extended loop,back mode. (See Chapter 1, Paragraph 1.3.4.)
Before the DEQNA is put in ELOOP or internal extended loopback mode, the receiver
must be disabled (see bit 00, below) and the receive FIFO emptied.
This bit is cleared by power-up initialization and software reset. It has no effect on set-up
mode. (See Chapter 1, Paragraph 1.3.4.)

IL -Internal Loopback. Read/write. This bit is active low. When asserted, it puts the
DEQNA into internalloopback mode. This bit must also be asserted to put the DEQNA
into internal extended loopback mode (see bit 09, above).
This bit is asserted by power-up initialization and software reset to prevent a failed DEQNA
from transmitting on the ETHERNET. It has no effect on set-up mode. (See Chapter 1,
Paragraph 1.3.4.)

XI - Transmit Interrupt Request. Read/write. When set by the DEQNA, this bit indicates
that the DEQNA has transmitted a packet and written the transmit status into the final
transmit buffer's descriptor. Software must clear this bit (write 1 to clear; write 0 has no
effect) to allow subsequent interrupt requests. Bit 02 must be checked at the same time as
this bit to differentiate between a transmit interrupt request (bit 07 set, bit 02 cleared) and
an NXM interrupt (bits 07, 05, 04, and 02 set). (See bits 02 and 06.)
This bit is cleared by power-up initialization and software reset.
NOTE
Interrupts are not queued. If the DEQNA processes
multiple messages before the interrupt request bit is
cleared, additional interrupts are not requested.

IE - Interrupt Enable. Read/write. When set, this bit allows the DEQNA to generate an
interrupt every time bit 07 or bit 15 goes from cleared to set. This bit is cleared by power-up
initialization and software reset. (See Chapter 1, Paragraph 1.3.3.)

RL - Receive List Invalid. Read only. When set, this bit indicates that the receive BDL is
empty. This bit is initialized in the set state by power-up initialization and software reset.

4-4

(See Chapter 1, Paragraph 1.3.3.) Setting bit 02 also sets this bit. It is cleared when the
high-order bits of the receive BDL starting address register are loaded; it is subsequently set
when the QDTC reaches the end of the receive BDL.
04

XL - Transmit List Invalid. Read only. When set, this bit indicates that the transmit BDL is
empty. This bit is initialized in the set state by power-up initialization and software reset.
(See Chapter 1, Paragraph 1.3.3.) Setting bit 02 also sets this bit. It is cleared when the
high-order bits of the transmit BDL starting address register are loaded; it is subsequently
set when the QDTC reaches the end of the transmit BDL.

BD - Boot/Diagnostic ROM. Read/write. When set, this bit causes one copy of the
boot/diagnostic ROM to be loaded into the receive FIFO for subsequent transfer to host
memory. Because the ROM is 4 Kbytes, the receive BDL must be set up for a minimum of
two 2 Kbyte buffers. Before this function is asserted, the receiver must be disabled (see bit
00) and the Receive FIFO emptied (done best by resetting the DEQNA). This bit must then
be asserted for at least 100 microseconds, or until the operation begins (determined by
polling the receive buffer's descriptor USING flag). (See Paragraph 4.3.2.1.) If the operation fails (by timing-out), the DEQNA is known to be bad. The ROM contents are validated
by a checksum which must be verified at the end of the load. There is no byte offset to the
PDP-II bootstrap and diagnostic code.
For normal operation to proceed, software must reset the DEQNA. Because explicit receive
status is not reported after the BD ROM data is transferred, and no interrupt is requested,
the length of the receive buffers should be exactly 4096 bytes. Completion is then indicated
by the USED status in the final buffer's descriptor flags. (See Paragraph 4.3.2.1.)
This bit is cleared by power-up initialization and software reset.

NI - Nonexistent Memory Interrupt. Read only. The DEQNA sets this bit when a time-out
occurs during a bus transaction. The setting of this bit also sets bits 04 and 05; that is, both
the transmit and receive BDLs are invalidated. The setting of this bit also sets bit 07,
causing an interrupt if bit 06, interrupt enable, is set.
This bit is cleared by power-up initialization, software reset, and when bit 07 is cleared.

SR - Software Reset. Read/write. This bit can be set or cleared under program control to
initialize the DEQNA. It holds the DEQNA initialized while it is set. This bit is cleared by
power-up initialization; however power-up initialization also holds the DEQNA initialized.
This bit and power-up initialization clear bits 00, 02, 03, 06, 07, 09, 10 and 15; and set bits
04, OS, and 08 (low).

RE - Receiver Enable. Read/write. When low (cleared), this bit disables the EPP receiver
in the EDLC. It does not disrupt a reception in progress and has no effect on any messages
queued in the receive FIFO. Its primary function is to synchronize certain other DEQNA
functions with ETHERNET packet reception (see bits 03 and 09). Transmit activity is
regulated by software via the transmit BDL.
This bit is cleared by power-up initialization and software reset; that is, the receiver is
disabled.

4-5

4.3 DMA TRANSFERS
The DEQNA transfers packet data to and from receive and transmit buffers in host memory. A transmit
buffer's length can be between 1 and 1514 bytes (the maximum number of bytes allowed in an
ETHERNET packet, less the four CRC bytes). A receive buffer's length can be between 2 and 2048
bytes. For adequate performance, receive buffers should generally be 64 bytes or larger, to reduce list
processing overhead. (When reading the BD ROM, a minimum of two 2-Kbyte receiver buffers are
required. See Paragraph 4.2.4, CSR bit 03.) Enough receive buffers to hold at least one packet of the
maximum expected length should always be allocated to ensure an interrupt on the next reception.
Transmit buffers can start and/or end on byte boundaries, but receive buffers must start and end on word
boundaries. A buffer can contain an entire packet or part of a packet, but it cannot contain more than one
packet. Buffers contain only data; buffer status is contained in the buffer descriptor. The buffers are
linked together by buffer descriptor lists (BDLs).
4.3.1 Buffer Descriptor List (BDL)
There are two descriptor lists: transmit BDL and receive BDL. The starting address of each BDL is written
into the port registers. (See Paragraph 4.2.2 and Chapter 1, Paragraph 1.3.1.) A descriptor list is a
forward-linked list of buffer descriptors.
4.3.2 Buffer Descriptor
The buffer descriptor format is shown in Figure 4-2, and described in the following paragraphs.

STATUS WORD 2
FLAG

ADDRESS DESCRIPTOR BITS

H.O. ADDR BITS

LOW ORDER ADDRESS BITS

ONE
DESCRIPTOR

BUFFER LENGTH
OMIT IF [
CHAIN
ADDRESS

STATUS WORD 1
STATUS WORD 2
FLAG
MR-12439

Figure 4-2

BDL Format

4.3.2.1 Flags - Only bits 15 and 14 in the flag word are defined (see Table 4-1). They and status word 1
bits 15 and 14 (see Table 4-3) are the buffer-ownership handshake/semaphore between the DEQNA and
host software. The bits are initialized by the software and written to Is by the DEQNA.
Table 4-1
Bit
15

Flag Word Bits 15 and 14

Definition

Initialized value. The DEQNA is not yet using this buffer.
The DEQNA is using this buffer.

4-6

4.3.2.2 Address - The high- and low-order address bits are either the 22-bit address of the buffer
associated with this descriptor, or the address of another descriptor (see address descriptor bit 14, below).
4.3.2.3 Address Descriptor Bits - The address descriptor bits define the attributes of the address, as
follows.
Bits

Definition

V - Valid. When set, this bit indicates that this descriptor contains a valid address. (See
Table 4-2 and bit 12, below.)

C - Chain Address. When set, this bit indicates that the address contained in this descriptor
is another descriptor's address. This allows the DEQNA to process multiple, non-contiguous
descriptor lists and explicitly "chain" the lists. Note that contiguous descriptors are implicitly chained. (See Table 4-2.)

E - End of Message. (Transmit buffer descriptor only) When set, this bit indicates that this
buffer contains the last segment of the packet. (The DEQNA will attempt to transmit the
entire frame after this segment is prefilled.)

S - Set-Up. (Transmit buffer descriptor only) When set, this bit indicates that the buffer
contains a list of DEQNA target addresses and control information (see Paragraph 4.3.3).
This bit must be cleared when bit 15 is cleared (invalid).

11 :08

Undefined.

L - Low Byte Only Termination. (Transmit buffer descriptor only) When set, this bit
indicates that this buffer ends on a byte boundary, instead of a word boundary.

H - High Byte Only Start. (Transmit buffer descriptor only) When set, this bit indicates
that this buffer starts on a byte boundary, instead of a word boundary.
NOTE
Both Hand L 'must not be set when the word count
is 1.

Table 4-2

Valid and Chain A~dress Descriptor Bits

Valid
15

Chain
Address
14

Definition

This is a valid buffer address.

This is a valid buffer descriptor address.

This address is now invalid (end of the BDL).

Reserved.

4-7

4.3.2.4 Buffer Length (Word Count) - Buffer length is the two's complement value of the number of
words in the buffer. If a transmit buffer is unaligned (that is, begins and/or ends on a byte boundary rather
than a word boundary), the unaligned byte(bytes) counts(count) as one word(words). (See address
descriptor bits 06 and 07, above. If both Hand L are set, the true word count must be increased by one.)
The word count does not include the four CRC bytes.
4.3.2.5 Status Words - At the end of a transmit or receive sequence, the DEQNA updates the two
status words in the final buffer's descriptor. (See Chapter 1, Paragraphs 1.3.6 and 1.3.7) Flag word bits 15
and 14 (see Table 4-1) and status word 1 bits 15 and 14 (see Table 4-3) are the buffer-ownership
handshake/semaphore between the DEQNA and host software. The bits are initialized by the software
and written to Is by the DEQNA. If transmit status shows an error, host software should attempt to
retransmit the packet, unless it was the second abort of the same packet with the same Time Domain
Reflectometer (TDR) value. The status word bits are defined in the following sections.
Transmit Status Word 1
Bit

Definition

LASTNOT. See Table 4-3.

ERROR/USED. Transmit ERROR is the logical OR of ABORT (bit 09), NOCAR (bit
11), and LOSS (bit 12). Also, see Table 4-3.
Table 4-3

Last-out
15

Error/Used
14

Status Word 1 Bits 15 and 14

Definition
Initialized value.
This buffer has not been used.
This buffer has been used but it is not the last segment of the message.

o
o

This buffer contains the last segment of a message with no errors.
This buffer contains the last segment of a message with errors.

Reserved. Read as 1.

LOSS. When set, indicates either loss of carrier during transmission or carrier was not
present within approximately 1.6 microseconds of the start of transmission (possible short
circuit in the ETHERNET cable). Sets bit 14.

NOCARrier. When set, indicates the carrier signal from the transceiver was not present
during transmission (possible problem in the transceiver or transceiver cable). Sets bit 14.
NOTE
Bits 11 and 12 validate the Encoder/Decoder (ED)
chip during internal loopbacks.

4-8

STE16. When set, indicates that the sanity timer was enabled at power-up, with a time-out
period of 4 minutes.

ABORT. When set, indicates that the transmission was aborted due to excessive collisions.
(See COUNT, bits 07:04.) Two ABORTS in a row with the same TDR valuee indicate a
probable short or open in the ETHERNET cable at a distance indicated by the TDR value.
(See bit 12, above, and transmit status word 2, below.) Sets bit 14.

F AIL. When set, indicates heartbeat collision check failure; that is, the transceiver failed to
return a collision pulse, either during the transmission or as a check after the transmission
(possible transceiver problem, or the transceiver does not have heartbeat circuitry). This bit
is set during internal loopback.

07:04

COUNT. The value of this 4-bit counter is the number of collisions that occurred before the
transmission attempt associated with this status word. A value of zero means that either
there were no collisions or that the transmission was aborted after 16 collisions. (See bit 09.)
Averaged over time, this value indicates network loading.

03:00

Reserved.

Transmit Status Word 2 - This word should not be considered valid until the following flag word is
written, or until it is non-zero (if it was initialized to zero).
Bit

Definition

15: 14

Reserved.

13:00

TDR. Time Domain Reflectometer 100 nanosecond resolution count. This is a count of bit
times (1 bit time = 100 nanoseconds), and is useful for locating a fault on the cable using
the velocity of propogation (approximately 5 nanoseconds per meter) on the cable. (Currently, with the DEQNA, approximately 500 nanoseconds must be subtracted for synchronization delays.) (See status word 1, bit 09.) A count greater than 511 indicates that the collision
which caused the ABORT was a late collision (that is, occurred after the slot time, where
slot time = 512 bit times), caused by a faulty node on the network.

Receive Status Word 1
Bit

Definition

LASTNOT. See Table 4-3.

ERROR/USED. Received ERROR is the logical OR of RUNT (bit 11), DISCARD (bit
12), LONG, and TYPE field (=09_00 hex) times DEST ADR (power-up value of an
EDLC 48-bit register). LONG indicates an illegally long packet, truncated at 1600 bytes.
See Table 4-3.

ESETUP. When set, indicates a looped-back control/set-up, ELOOP, or IELOOP packet.

DISCARD. When set, indicates that OVF (bit 00), CRCERR (bit 01), and SHORT (bit 03)
are valid (that is, they pertain to this packet). This bit is never set unless one of the other
three bits is set. Sets bit 14.

4-9

RUNT. When set, indicates the remains of a packet were loaded in the receive FIFO and
could not be flushed because the FIFO also contained good data. This happens (occasionally) from collision fragments target address match failures, and CRC error on a packet less
than 69 bytes long. (See Chapter 1, Paragraph 1.3.7.) Software should discard the frame,
and repost (reallocate) the buffers. This bit is cleared for control/set-up and ELOOP
packets. Sets bit 14.

10:08

RBL <10:08>. Received Byte Length bits 10 thru 08. See receive status word 2, bits 07:00.
These bits are all set during set-up mode packet processing.

07:03

Reserved.

FRAME. When set, indicates a Framing Alignment Error; that is, other than an integral
number of bytes were received. This bit is only set if there was also a CRC error. See bit 12.

CRCERR. When set, indicates a CRC error has been detected and the message has been
truncated by one to six bytes. This bit is valid only if DISCARD (bit 12) is set. Runts
caused by a collision usually have this bit set. (See bit 11.) See bit 12.

OVF. When set, this bit indicates that the ETHERNET Protocol Processor (EPP) overflowed, and one or more messages were lost between the current message and the previous
message. This bit is valid only if DISCARD (bit 12) is set. The current message is intact if
both DISCARD and RUNT (11) are not set. EPP overflow can be caused by the following
conditions.
•

Receive FIFO overflow.

•

Coming back on-line after the receive enable (CSR bit 00) bit was negated, and
internal loopback (CSR bit 08) is not asserted.

•

Reading the BD ROM, and internalloopback (CSR bit 08) is not asserted.

•

Being in external loopback mode.

In external loopback mode, this bit is set only if ETHERNET traffic is lost. This bit is
undefined after power-up or reset. See bit 12.
Receive Status Word 2 - This word must be initialized to have unequal high and low bytes. It is then valid
when the bytes match.
Bit

Definition

15:08

RBL <07:00>. Receive Byte Length bits 07 through 00. Duplicated from lower byte.

07 :00

RBL <07:00>. Receive Byte Length bits 07 through 00. These bits and receive status word
1 bits 10:08 (above) form RBL <10:00>, the number of bytes transferred into the receive
FIFO. Software adds 60 to this value, to account for the period during which address
filtering occurs. The 4-byte CRC is not included in the count; CRC is not transferred to the
FIFO.
If the RBL is greater than the maximum packet length (1514 bytes without CRC), it is
truncated at a maximum value of 1596 bytes. That is, an RBL value of 1536 plus the 60
bytes added by software.

4-10

4.3.3 Set-Up Mode
Set-up mode is a control and status function performed as a DMA transfer. The mode is entered when
address descriptor Bit 12 is set in a transmit buffer descriptor. (See Paragraph 4.3.2.3.)
A set-up packet contains control information and is not transmitted over the ETHERNET, but is stored in
the DEQNA. The maximum set-up packet size is 256 bytes. At least the first 112 bytes of control
information must be initialized before the receiver is enabled (CSR bit 00 set). The states of ILOOP (CSR
bit 08) and ELOOP (CSR bit 09) have no effect on set-up mode.
A set-up packet defines DEQNA target addresses and operating conditions. Its buffer descriptor has the
same format as a normal transmit buffer descriptor (see Figure 4-2), but the buffer length word is
in terpreted differen tl y.

4.3.3.1 Target Address Set-Up - Buffer length values between 000 and 177 (octal) are the target
address byte count. These 128 bytes are formatted as shown in Figure 4-3.

BYTE OFFSET
BYTE
(OCTAL)
000

010
020
030
040

ix •

•

TARGET ADDRESS

070

X
X

100
110
120
130
140

Ix •

050

060

150

160
170

x
~

TARGET ADDRESS

X
X

x = BYTE IS ALL O's
MR-12443

Figure 4-3

Target Address Set-Up

For example, the figure shows that the six bytes of target address 12 are contained in buffer bytes 105,
115, 125, 135, 145, and 155. The low-order byte is the lowest numbered byte (that is, the bytes in rows
000 and 100). The low-order bit of the low-order byte is the address's multicast bit.
At least one address must be the node's default physical address, and one must be the broadcast address
(all Is). Any other specified addresses must be multicast addresses (low-order bit of low-order byte set).
Any unused addresses should be set to the default physical address, to protect against spurious
ETHERNET traffic.

4-11

4.3.3.2 Operating Condition Set-Up - When the byte exceeds 128 (177 octal), bits 06:00 of the byte
count are used as control parameters, and are interpreted as follows.
Bit

Definition

All Multicast. When set, enables the DEQNA to recognize any multicast address.

Promiscuous. When set, enables the DEQNA to recognize any destination address.

03:02

LED Value. These two bits cause the three LEDs on the DEQNA to turn off in the
following sequence (all the LEDs are turned on at power-up and when boot/diagnostic code
is loaded from the BD ROM).

06:04

No effect.

Turns off the first LED, indicating the DEQNA self-test is running in the host.

Turns off the second LED, indicating all internal loopbacks appear to function
correctly.

Turns off the third LED, indicating externalloopback appears to function correctly.

Sanity Timer Time-Out Value. Determines the time-out period of the sanity timer by
increasing its value. The value is increased in factors of four, as follows.
000 = 1/4 second
001 = 1 second
010 = 4 seconds
011 = 16 seconds
100 = 1 minute
101 = 4 minutes
110 = 16 minutes
111 = 64 minutes

4.3.3.3 Set-Up Packet - If a set-up packet contains 128 bytes or less, only the target addresses are
modified. Any such short packet should not end in the middle of an address; therefore, useful set-up
packet lengths are 48 through 64 bytes and 112 through 256 bytes.
The set-up packet is looped-back internally and loaded into a receive buffer for verification and synchronization. ETHERNET transmissions are disabled until the loopback is complete and the next transmit
buffer descriptor is accessed.

4-12

APPENDIX A

GLOSSARY

Baseband Coaxial System: A system where information is directly encoded and placed on the coaxial
medium. One information signal at a time can present on the medium without disruption (see collision).
Binary Exponential Backoff: The algorithm used to schedule retransmissions after a collision. So named
because the interval between retransmissions is increased exponentially with repeated collisions.
Bit Cell: The length of time occupied by one encoded data bit (see Manchester encoding). Equivalent to bit
time.
Bit Time: Equivalent to bit cell. At 10 MHz the bit time is 100 ns.
Broadcast: In general, the mode of communications where all nodes are capable of receiving a signal
transmitted by any other node. Also, a specific ETHERNET addressing mode where the destination is all
nodes.
Carrier Sense: The means by which the physical layer determines that one or more nodes are currently
transmitting on the ETHERNET.
Citizenship Test: PDP-II code contained in the DEQNA BD ROM. This is a "go/no-go" diagnostic for
the DEQNA, executed by the host.
Coaxial Cable: A two-conductor, concentric, constant impedance transmission line.
Coaxial Cable Interface: The electrical, mechanical, and logical connection to the coaxial cable medium.
In other words, the transceiver.
Coaxial Cable Section: An unbroken piece of coaxial cable, fitted with coaxial connections at its ends,
used to make up coaxial cable segments.
Coaxial Cable Segment: See segment.
Collision: The result of simultaneous transmissions by multiple nodes. Simultaneous transmissions cause
garbled data and require that data be retransmitted.
Collision Detect: The indication that one or more other nodes' transmissions are in contention with the
local node's transmission. Collision detect is asserted only during transmission.
Collision Enforcement: Transmission of extra, encoded "jam" bits (that is, the continued transmission of
encoded frame bits) after a collision is detected. This makes the duration of the collision long enough to be
detected by all transmitting stations.

A-I

Contention: Interference between colliding transmissions (see collision). Resolution of contention is part of
ETHERNET link management (see CSMAjCD).
Controller: The unit which connects a node to the ETHERNET (for example, the DEQNA).
CSMAjCD: Carrier Sense Multiple Access with Collision Detection - the generic term for the class of
link management procedure used by the ETHERNET. So called because it:
•
•
•

allows multiple nodes to access the broadcast channel at will
avoids contention through carrier sense and deference
resolves contention through collision detection and retransmission.

Data Link Layer: The higher of two layers in the ETHERNET design. It implements a mediumindependent link level communications facility on top of the physical channel provided by the physical
layer.
DECnet Boot: PDP-II code contained in the DEQNA BD ROM. This is part of the BD ROM MOP code,
and, when called, starts DECnet.
Deference: A process by which the DEQNA delays transmission when the channel is busy to avoid
contention with on-going transmissions.
DEQNA Primary Boot: The DEQNA-specific part of the primary bootstrap code in the host.
Destination Address: The 48-bit packet field containing the receiving node's address.
Extended Primary Bootstrap: PDP-II code contained in the DEQNA BD ROM. It "uploads" the entire
contents of the BD ROM into host memory (after the DEQNA primary bootstrap has loaded it and
transferred control to it), calls the citizenship test, and either:
•
•
•

halts if an error occurs, or
calls the DEC net boot, or
dispatches to a user-supplied address.

Frame: See packet.
Frame Check Sequence: An encoded value at the end of each frame that allows detection of transmission
errors in the physical channel.
Frame Fragment: Any frame containing less than 64 bytes (512 bits) is defined to be a frame fragment
resulting from a collision. See runt.
Heartbeat: A positive, functional verification provided by the H4000 transceiver after every attempted
transmission. It indicates that the H4000 is operating correctly with respect to collision detection.
Host: The processing system to which the DEQNA is connected.
Interframe Spacing: see interpacket gap.
Interpacket Gap: An enforced idle time between successive transmissions to allow receiving controllers and
the physical channel to recover.

A-2

Jam: An encoded bit sequence (for example, part of the frame) transmitted to enforce a collision. A jam
comprises at least 32 but not more than 48 bits.
Late Collision: A collision that occurs at least one slot time after the start of transmission.
Manchester Encoding: A self-synchronizing method of encoding a serial data stream, such that a phase
reversal occurs in the center of every bit-cell.
Message: See packet.
Multicast: An addressing mode where the destination is a group of nodes.
Node: A single addressable ETHERNET site (for example, a computer and its peripherals) connected to
the ETHERNET via a controller (for example, DEQNA) and a transceiver.
Packet: All data carried on the ETHERNET is encapsulated in a packet (also called frame) containing a
preamble, destination address field, source address field, type field, data field, and frame check sequence.
Packets are separated by the inter-packet gap.
Physical Address: The unique address value of a given node on the network. By definition, an
ETHERNET physical address is distinct from all other physical addresses on all ETHERNETs.
Physical Channel: The implementation of the physical layer. For example, the DEQNA, transceiver cable,
transceiver, and coaxial cable.
Physical Layer: The lower of the two layers in the ETHERNET design. The physical layer is implemented in the physical channel using the specified coaxial cable medium. It insulates the data link layer from
medium-dependent physical characteristics.
Preamble: A 64-bit sequence transmitted at the start of a frame for receiving-node synchronization.
Primary Bootstrap: Host resident (usually contained in ROM) PDP-II code that is executed when the
system is powered-up.
Promiscuous Mode: A reception mode. In this mode, the controller accepts all packets and address
filtering is done by host software.
Repeater: A device for connecting cable segments and extending the physical channel up to the maximum
end-to-end channel length.
Round-trip Propagation Time: The worst-case time (in bit times) required for a transmitting node to assert
collision detect due to normal contention for the channel. This time is the primary component of slot time
and is defined to be 464 bit times (45.4 microseconds).
Runt: The status of a partial packet that exists in the receive FIFO because either the packet's destination
address did not match this node's address or a collision occurred during packet reception, and the FIFO
could not be flushed.
Segment: A length of coaxial cable made up from one or more coaxial cable sections and terminated at
each end in its characteristic impedance. The maximum segment length is 500 meters (1640.5 feet).

A-3

Slot Time: A parameter that describes the three important aspects of collision handling, it is:
•
•
•

An upper bound on the acquisition time of the network
An upper bound on the length of a collision-generated frame fragment
The base value used to calculate the retransmission delay.

Slot time is defined to be 512 bit times (51.2 microseconds).

Source Address: The 48-bit packet field containing the transmitting node's address.
Station: Equivalent to node.
Station Address: See physical address.
Transceiver: The device that connects directly to the coaxial cable and provides the electronics which send
and receive the encoded signal on the cable as well as providing the required electrical isolation (for
example, the H4000).
Transceiver Cable: The cable between an ETHERNET controller, such as the DEQNA, and a
transcei ver.
Transceiver Cable Bulkhead Assembly: An assembly comprising the transceiver cable, transceiver fuse,
and patch and filter panel assembly insert.
Type: The 16-bit packet field that indicates how higher layers in the architecture are to interpret the data
field.

A-4

APPENDIX B
VECTOR AND I/O PAGE ADDRESS ASSIGNMENTS

This appendix lists vector and I/O page address assignments for MICRO/PDP-II systems. Assignments
implemented on the MICRO/J-11 but not on the MICRO/F-11 are indicated with an asterisk (*).
Specifically assigned device vector and I/O page addresses should be used first; additional device addresses
and vectors should be assigned in the floating Control/Status Register (CSR) area, 17760010-17763776,
and the floating vector area, 300-776.
A rank is assigned to every device eligible for the floating CSR and floating vector areas. The highest
ranked (lowest number) device is assigned the first CSR address (17760010) or vector address (300);
subsequent devices are assigned addresses in ascending order. Note that a device may use both fixed and
floating vectors and addresses; and that the assigned rank may be different for a device's floating address
and floating vector.
Table B-1

Interrupt and Trap Vector Assignments

Address
(Octal)

Function

004
010
014
020
024
030
034
060
064
100
124
160
200
240*
244
250
264
300-377

Bus time-out and illegal instructions
Illegal and reserved instructions
BPI instructions and trace trap
IDT instruction
Power-fail
EMT instruction
TRAP instruction
Console terminal input
Console terminal output
External event line interrupt
DRV11-B parallel interface
RL V 12 disk controller
LPV11 line printer
PIRQ
Floating-point error
Memory management
RXV21 floppy disk
Floating vectors

*MICRO/J-ll

B-1

Table B-2

I/O Page Addresses

Address (Octal)

Function

17760010-17763776
17764100-17764106
17764110-17764116
17764120-17764126
17767740-17767742
17767744-17767746
17767750-17767752
7770400
7770420
17770420-17770421
17770440
17770450
17772200-17772216*
17772220-17772236*
17772240-17772256*
17772260-17772276*
17772300-17772316
17772320-17772336*
17772340-17772356
17772360-177772376*
17772410
17772420
17772430
17772516
17773000-17773776
17774400
17774440-17774456
17774460-17774476
17775610-17776476
17776500-17776676
17777170
17777512
17777520-17777524
17777546
17777560
17777514
17777572
17777574
17777576
17777600-17777616
17777620-17777636*
17777640-17777656
17777660-17777676*
17777746*
17777752*
17777766*
17777772*
17777776

Floating addresses
DRVII-J No.1
DRVII-J No.2
DRVII-J No.3
DRVII No.3
DRVII No.2
DRVII No.1
ADVII
KWVII-A
ADVII No.2, AXVII No.2, KWVII-C
AAVII
ADVII No.1, AXVII No.1
Supervisor Mode I Space PDR 0-7
Supervisor Mode 0 Space PDR 0-7
Supervisor Mode I Space PAR 0-7
Supervisor Mode 0 Space PAR 0-7
Kernel Mode I Space PDR 0-7
Kernel Mode 0 Space PDR 0-7
Kernel Mode I Space PAR 0-7
Kernel Mode 0 Space PAR 0-7
DRVII-B No.1
DRVII-B No.2
DRVII-B No.3
Memory Management Status Register 3
KDFII-B Boot/Diagnostic ROM
RLVll, RLV12
DEQNA No. 1 Port Control Block (PCB)
DEQNA No.2 Port Control Block (PCB)
Bl Serial Line Units with Modem Control (DLVII-E)
16 Serial Line Units without Modem Control (DLV II-J)
RXV21 Diskette Controller
Line Printer (LPV 11)
KDR 11-B Boot/Diagnostic Registers
Line Time Clock
Console Terminal
LPVll
Memory Management Status Register 0
Memory Management Status Register 1
Memory Management Status Register 2
User Mode I Space PAR 0-7
User Mode 0 Space PDR 0-7
User Mode I Space PAR 0-7
User Mode 0 Space PDR 0-7
Cache Control Register
Hit/Miss Register
CPU Error Register
Program Interrupt Request Register (PIR)
Processor Status Word (PSW)

*MICROjJ-ll

B-2

Table B-3
Rank

Device

2
8

DLVII-J
DRVII-B
DRVII
DLVII-E
KXVII
DUVII
DZVll
RLV12
RXV21
DPVll
DMVII
DEQNA

9
14
20

26
27
34
9
43
46
47

Parallel Line Interface
DMA Interface
Parallel Line Interface
Asynchronous Serial Line Interface
Programmable Real-time Clock
Synchronous Serial Line Interface
4-line Asynchronous Serial Line Multiplexer
RLOljRL02 Disk Controller
Diskette Controller
Synchronous Serial Line Interface
DECnet Synchronous Serial Line Interface
ETHERNET Q-Bus Adapter

Table B-4
Rank

Device

2
8
14
18
21
24

DUVII
DZV11
RLVll,12
RXV21
DPV11
DMV11

Floating Vector Rank

Floating Address Rank

Synchronous Serial Line Interface
4-line Asynchronous Serial Line Multiplexer
RLO 1jRL02 Disk Controller
Diskette Controller
Synchronous Serial Line Interface
DECnet Synchronous Serial Line Interface

B-3

APPENDIX C
NETWORK INTERCONNECT EXERCISER

This appendix is an overview of the Network Interconnect Exerciser (NIE) program for the DEQNA. For
more information refer to the user's manual for CVNIAAO DEQNA NI Exerciser Diagnostic,
(AC-T585A-MC).
C.I INTRODUCTION
The NIE diagnostic program is used to determine the connectivity of nodes on the ETHERNET. It
determines the ability of nodes to communicate with each other, and supports node installation verification
and problem isolation.
The NIE does not test the device (DEQNA), but the communications link to which it is connected;
therefore, the NIE assumes that the DEQNA has passed device-specific diagnostics. If any hardware
errors occur during execution, the NIE reports the error by message to the operator. Unless command to
halt on error (see Paragraph C.4.I.2), the NIE resumes testing where it left off after reporting the error.
However, note that the NIE does not test the DEQNA to its performance limits, diagnose problems,
provide comprehensive hardware testing, nor identify a failed FRU.
The NIE runs under control of the PDP-II Diagnostic Runtime Services (DRS) software (supervisor);
therefore, it cannot run concurrently with any operating system, nor can anyone else use the system while
the NIE is running. In addition, overall performance of the ETHERNET can be degraded by running the
NIE.
The DRS provides the interface to the operator and to the software environment. The NIE can be used
with XXDP+, ACT, APT, and paper tape. Paragraph C.4.l gives a brief description of DRS commands;
for a complete description of DRS, refer to the XXDP+ User's Manual.
C.2 OPERATING MODES
The NIE is command-driven; that is, it executes commands given by the user. (Commands are described
in Paragraph C.4.) In addition to entering commands, the user can select one of two operating modes:
unattended or operator directed.
C.2.1 Unattended Mode
This mode allows ETHERNET testing without operator interaction. The tests share a table comprising the
physical addresses of the nodes to be tested (Node Table), and use default test parameters that cannot be
modified by the operator. The unattended mode:
1.
2.
3.
4.
5.
6.

Runs internal loop test
Runs external loop test
Builds node table
Runs direct loop message test
Runs pattern test
Runs mUltiple message activity test

C-l

C.2.1.1 Build Node Table - The build subroutine is called to collect the physical addresses of the
ETHERNET nodes. It begins by transmitting a Request ID message on the ETHERNET, to find a node
to test. As the other nodes respond with their IDs, the NIE collects the IDs and adds the nodes to the node
table, to include them in the tests.
C.2.1.2 Direct Loop Message Test - This test checks the ability of a node to respond to a loopback
request. (See Paragraph CA.2, RUN TEST command, DIRECT test.) A node has a maximum of 8
seconds to respond; three attempts are made to contact each node.
C.2.I.3 Pattern Test - This test sends six different loop direct messages to each node in the node table.
(See Paragraph CA.2, RUN TEST command, PATTERN test.)
C.2.1.4 Multiple Message Activity Test - This test uses the direct loop maintenance feature to create a
large volume of ETHERNET traffic. Loopback requests are sent to a subset (for example, 10) of the
available nodes. All nodes in the subset are expected to respond, but data integrity is checked for only one
of the responses (to save overhead). Upon successful completion, testing continues, checking the response
from a different node each time. After all the nodes in the subset have been tested, testing continues with a
different subset. This test is expected to cause multiple collisions and can affect overall ETHERNET
performance.
C.2.2 OperatOt' Directed Mode
The commands available in this mode are listed below and described in Paragraph CA.2.
•
•
•

HELP
BUILD
CLEAR
MESSAGE
NODE
SUMMARY

•
•
•
•

IDENTIFY
MESSAGE
NODE
RUN TEST
DIRECT
LOOPPAIR
PATTERN
ALL

•
•
•

SAVE
UNSAVE
SHOW
COUNTERS
MESSAGES
NODES

•
•

SUMMARY
EXIT

C-2

C.3 SYSTEM REQUIREMENTS
The following hardware is the minimum required to run the CVNIA NIE program.
•
•
•
•
•
•

LSI-II processor
28 Kwords memory
Event line enabled or real-time clock
Console terminal
Any XXDP+ supported load media
DEQNA ETHERNET to Q-Bus Adapter (minimum of 1, maximum of 2; tested individually)

The NIE uses XXDP+ as the program loading system and the PDP-II Diagnostic Runtime Services
(DRS) for the program environment.
C.4

COMMAND DESCRIPTION

C.4.1 DRS Commands
The 11 DRS commands are listed in Table C-l, with a brief description of each. The system will recognize
a command by its first three characters; for example, you can type STA instead of START.

Table C-l

DRS Commands

Command

Description

START

Start the diagnostic from an initial state.

RESTART

Start the diagnostic without initializing.

CONTINUE

Continue at test that was interrupted (after <CTRL>C).

PROCEED

Continue from an error halt.

EXIT

Return to XXDP+ monitor (XXDP+ operation only).

ADD

Activate a unit for testing (all units are considered active at START time).

DROP

Deactivate a unit.

Print statistical information (if implemented by the diagnostic).

DISPLAY

Type a list of all device information.

FLAGS

Type the state of all flags (see Paragraph C.4.1.2).

ZFLAGS

Clear all flags (see Paragraph C.4.1.2).

C-3

CA.1.1 Switches - Several switches can be appended to DRS commands, to modify supervisor operation. The switches are defined in Table C-2, with a brief description of each. (Note: ddddd = 1 to 65535
decimal.) The switches can be used in combination. For example:

START/TESTS: 1-5/PASS: 1000 /EOP: 100
will cause tests 1 through 5 to execute; all units will be tested 1000 times; and the end of pass messages will
be printed only after every 100 passes. The system will recognize a switch by its first three characters. For
example, you can type /TES: 1-5 instead of /TESTS: 1-5.
Table C-3 lists the switches that can be used with each command.
Table C-2

DRS Command Switches

Switch

Description

/EOP:ddddd

Report End of Pass message only after every ddddd passes.

/FLAGS:flag

Set specified flag(s) (see Paragraph CA.1.2).

/PASS:ddddd

Execute ddddd passes.

/TESTS:list

Execute only the tests specified by list (a string of test numbers). For example:
START/TESTS: 1:5:7-10
will run tests 1, 5, 7, 8, 9, and 10. No other tests will be run.

/UNITS:list

Test/ ADD/DROP only those units (0-63) specified by list. For example:
ST ART/UNITS:0:5: 10-12
will test units 0, 5, 10, 11, and 12

Table C-3

Switch Application

Commands

Tests

Switches
Pass

START
RESTART
CONTINUE
PROCEED
EXIT
ADD
DROP
PRINT
DISPLAY
FLAGS
ZFLAGS

X
X

X
X
X

Flags

EOP

Units

X
X
X
X

X
X
X

X
X

(none)
X
X
(none)
X
(none)
(none)

C-4

C.4.1.2 Flags - Flags are used to set-up certain operational parameters, such as looping on error. All
flags are cleared:
1.

2.
3.

at startup and remain cleared until explicitly set with the /FLAGS switch
after a START command unless set with the /FLAGS switch
with the ZFLAGS command.

No other commands, without a /FLAGS switch, affect the state of the flags; they remain as specified by
the last /FLAGS switch. The flags are listed and described in Table C-4.
Flags can be specified in combinations. For example:
/FLAGS:LOE:IER:BOE
causes the program to loop on error, inhibit error reports, and sound the bell on error.

Table C-4

DRS Command Flags

Flag

Effect

ADR

Execute autodrop code.

BOE

Sound bell on error.

EVL

Execute evaluation (on diagnostics which have evaluation support).

HOE

Halt on error - control is returned to DRS command mode.

IBE*

Inhibit all error reports except first level (first level contains error type, number, PC, test
and unit).

IDR

Inhibit program dropping of units.

IER*

Inhibit all error reports.

ISR

Inhibit statistical reports (applies only to diagnostics which support statistical reporting).

IXE*

Inhibit extended error reports (those called by PRINTX macros).

LOE

Loop on error.

LOT

Loop on test.

PNT

Print test number as test executes.

PRI

Direct messages to line printer.

UAM

Unattended mode (no manual intervention).

*Error messages are described in Paragraph C.5.I.

C-5

C.4.1.3

Hardware and Software Questions - When a diagnostic is started, the DRS types the prompt:

CHANGE HW (L) ?
asking for hardware information. If hardware information has been preloaded (using the set-up utility see the XXDP+ User's Manual), the correct response is N (no); otherwise, the response is Y (yes).
CHANGE HW (L) ? Y <CR>
(In this and all following dialogue examples, the user response is indicated by boldface.) After the Y
response, the DRS asks for the number (decimal) of units and proceeds to ask questions about each unit, as
follows.

# UNITS (D) ? 1<CR>
UNIT 0
DEVICE CSR ADDRESS: (O)? 174440<CR>
INTERRUPT VECTOR ADDRESS (O)? 300<CR>
INTERRUPT PRIORITY: ? (O)? 5<CR>
After the hardware questions are answered, or following a RESTART or CONTINUE command, the
DRS types:
CHANGE SW (L) ?
to ask for software parameters. These parameters control some diagnostic-specific operation modes. If you
type N in response, you will be at the NIE command level. If you type Y, a question/answer dialogue
follows. (For another typical dialogue, refer to Chapter 3, Paragraph 3.2.3.3.2 and 3.2.3.3.3.) When you
complete the sequence, you will be at the NIE command level.
C.4.2 NIE Commands
The NIE command level is entered after attaching to the device and giving the START command to the
DRS. NIE commands are typed in response to the prompt:
NIE> (A) ?
The commands are interpreted from left to right; and you need type only enough characters to uniquely
specify a command. Command descriptions and examples follow.
Command

Description

HELP or?

Types a brief description of NIE commands.
Example:
NIE> (A) ? H
or
NIE> (A) ? ?

C-6

BUILD

This command is used to build the node table. It causes the exerciser to
listen for system ID messages (broadcast by all nodes every 10 minutes). All
such identifying nodes are added to the node table. The command stops if
no new nodes have been added for 10 minutes or 40 minutes have elapsed.
The average time for this command should be 15 to 25 minutes.
It is possible to miss a transmission within the 10 minute period. Therefore,
if no nodes appear in the table after a BUILD, wait 4 or 5 minutes and retry
the BUILD.
Example:
NIE> (A)? BU

CLEAR MESSAGE

This command resets message parameters to the default values.

CLEAR NODE/ ADR

This command clears the specified node from the node table. The node can
be specified by either its 12-digit (hex) physical address or its logical name
(from the node table). To find the logical name associated with an address,
execute the SHOW NODE command.

CLEAR NODE/ALL

This command clears the node table.
Examples:
Clear a node using its ETHERNET address:
NIE> (A) ? CL N/ AA-OO-04-FF-FF-FO
Clear a node using its logical name:
NIE> (A) ? CL N/N3
Clear all nodes:
NIE> (A) ? CL N/ ALL
A cleared node can be restored to the node table with the UNSA VE
command.

CLEAR SUMMARY

This command clears the summary table.

IDENTIFY ADR

Sends a Request ID message to the node specified by ADR. The returned
system ID parameters are typed.
Example:
NIE> (A) ? ID AA-OO-04-FF-FF-FO

C-7

MESSAGE/TYPE=
/SIZE=n/COPIES=m

This command allows the operator to select the current message parameters. Any or all parameters can be changed. The default parameters are:
/TYPE=ALPHA/SIZE=512/COPIES= 1.
The size of the message buffer is between 46 and 512 bytes. The number of
copies of each message sent to each node can be between 1 and 255 copies.
The message types are listed in Table C-5.
Examples:
Change type:
NIE> (A) ? M/T=ZERO
Change size:
NIE> (A) ? M/B=256
Change both size and type:
NIE> (A) ? M/B=512/T=ALPHA

Table C-5 NIE Test Message Types
Type

Content

ALPHA

!"#$%'O*+,-./0123456789;:=?ABCDEFG... etc.

ONES

All ones (11111111 .... ).

ZEROS

All zeros (00000000 .... ).

lALT

Alternating ones and zeros (10101010 ... ).

OALT

Alternating zeros and ones (01010101. .. ).

CCITT

International Telegraph and Telephone Consultation Committee pseudo-random test
pattern.

OPERATOR
SELECTED

Operator selected pattern of less than 72, characters using 0-9, A-Z, and spaces (not
used in PATTER)

C-8

NODE ADRjTYPE

This command allows the operator to enter nodes into the node table. Nodes
are specified by their 12-digit (hex) ETHERNET physical address; and can
be further specified (by jTYPE) to be either target or assist (default =
target). Before changing a node's type, the node must first be cleared from
the node table (see CLEAR command).
Examples:
Enter target node:
NIE> (A) ? N AA-OO-04-FF-FF-FO
or
NIE> (A) ? N AA-OO-04-FF-FF-FOjT
Enter assist node:
NIE> (A) ? N AA-OO-04-FF-FF-FOj A
Change a target node to an assist node:
NIE> (A) ? CL Nj AA-OO-04-FF-FF-FO
NIE> (A) ? N AA-OO-04-FF-FF-FOj A

RUN TESTjPASS=nn

Causes the specified test to execute for nn passes (default PASS = O. If nn
-1, (??? says G in the example below) the test will run indefinitely. Prior
to running the test(s), the NODE command should be used to enter the
node addresses (taken from the node table) to be tested. The LOOPPAIR
test requires node pairs, specified as target and assist nodes. Each test uses
the currently selected values for message type, size, and copies. The tests
are as follows.
=

DIRECT - This test sends a loop direct message to all of the nodes in the
node table, waits for a response, checks returned data integrity, and reports
any errors to the operator. The message to the target node comprises
encapsulated forward and reply messages. The response from the target
node comprises the same reply message. (See Figure C-l.)
LOOPPAIR - This test sends transmit, receive, and full assisted loopback
messages, comprising encapsulated forward and reply messages, to the node
pairs in the node table. (See Figures C-2, C-3, and C-4.) In each case, the
test waits for a response and checks the data.
PA TTERN - This test sends six different loop direct messages to each node
in the node table. Each of six message types (ALPHA, ONES, ZEROS,
1ALT, GALT, CCITT - see Table C-5) is sent to each node. Returned data
is checked for errors.

C-9

--------------.. ~

FORWARD

NI/ETHERNET

(2)1 •

NI
EXERCISER
NODE

TARGET
NODE

NOTE: NUMBERS INDICATE SEQUENCE IN WHICH MESSAGES ARE SENT
MR-12465

Figure C-l

Loop Direct Message Test Path

~ ~.~--------

NI/ETHERNET

FORWARD

•

NI
EXERCISER
NODE

FORWARD

•

NODE A
LOOP ASSIST

(2)
NODE B
TARGET

NOTE: NUMBERS INDICATE SEQUENCE IN WHICH MESSAGES ARE SENT
MR·12466

Figure C-2

Transmit Assist Loopback Message Test Path

C-IO

----------------------~. ~
REPLY

FORWARD

NI/ETHERNET

NI
EXERCISER
NODE

FORWARD

I REPLY I
NODE B
TARGET

NODE A
LOOP ASSIST

NOTE: NUMBERS INDICATE SEQUENCE IN WHICH MESSAGES ARE SENT
MA-12467

Figure C-3

Receive Assist Loopback Message Test Path

----------------------~. 0

--------------------------------~. ~
REPLY

FORWARD

0NI
EXERCISER
NODE

FORWARD

•

NODE A
LOOP ASSIST

I
NODE B
TARGET

NOTE: NUMBERS INDICATE SEQUENCE IN WHICH MESSAGES ARE SENT
MA-12468

Figure C-4

Full Assist Loopback Message Test Path

C-ll

ALL - This two-part test performs the most extensive check of the network. It sends a loop direct message to each node in the node table. If this is
successful, the exerciser builds an array of node pairs and sends a full
assisted loopback message to each pair in the array. Table C-6 shows a
sample array of pairs for a node table with seven nodes.
Table C-6
1-2

2-3

1-3
1-4
1-5

2-4
2-6

1-6

2-7

2-5

Node Pair Array

4-5

3-4
3-5
3-6
3-7

4-6
4-7

5-6
5-7

6-7

1-7
RESP - The RESPONDER test is a section of code that provides loopserver functions, such as: forwarding messages, answering console ID
requests, and transmitting a system ID every 8 to 9 minutes. This must be
run to use the DEQNA as a loop assist or target node on the ETHERNET.
The other tests ignore forwarding requests, and will not transmit console
IDs.
Examples:
Run the DIRECT test for one pass:
NIE> (A)? R D
Run the DIRECT test for 5 passes:
NIE> (A)? R DjP=5
Run the DIRECT test for infinite passes:
NIE> (A)? R DjP=O
??? command description, above, says P=-l ???
Run the LOOPPAIR test:
NIE> (A)? R L
Run the RESPONDER test:
NIE> (A)? R R
NOTE
The only way to end a large or infinite number of passes is to type
<CTRL>C. However, be careful: type REST ART in response to DSR>
(after the <CTRL>C), to return to the NIE> prompt and preserve the
counters. If you type START in response to DSR> after the <CTRL>C,
you will destroy all summary statistics and counters.

C-12

SAVE

This command saves the contents of the node table. The VAX NIE saves
the table in file NIE.TBL;*. The PDP-II NIE cannot write to external
media, and saves the contents internally.
Example:
NIE> (A) ? SAV
USED TO LEAVE THE NIE.
EXAMPLE:
NIE> (A) ? EXIT

C.S

ERRORS

C.S.I Error Messages
The three levels of error messages that a diagnostic can issue are: general, basic, and extended.
C.S.I.I General - General error messages are always typed unless the IER flag is set. The format is as
follows.
NAME TYPE NUMBER ON UNIT NUMBER TST NUMBER PC:xxxxxx
ERROR MESSAGE
where:
NAME
TYPE
NUMBER
UNIT NUMBER
TST NUMBER
PC:xxxxxx

diagnostic name
error type (system fatal, device fatal, hard or soft)
error number
o through n (n is last unit in PTABLE; that is, device information table)
test and subtest where error occurred
address of error message call

C.S.1.2 Basic - Basic error messages contain some additional information about the error. These are
always typed unless the IER or IBR flag is set. These messages are typed after the associated general error
message.
C.S.1.3 Extended - Extended error messages contain supplementary error information, such as register
contents or good/bad data. These are always typed unless the IER, IBR, or IXR flag is set. These
messages are typed after the associated general error message and any associated basic error messages.
Examples:
Lost packet error during LOOPPAIR testing:
CVNIA HRD ERR 00028 ON UNIT 00 TST 001 SUB 000 PC:064442
TIMEOUT OCCURRED - LOOP MESSAGE TYPE - RECEIVE ASSIST
FAILING TARGET NODE ADDRESS: AA-00-03-00-00-00
FAILING ASSIST NODE ADDRESS: AA-00-03-00-00-02
Lost packet error during PATTERN testing:

C-13

Command

Description

UNSAVE

This command restores the contents of the node table. The VAX NIE
restores the contents from file NIE. TBL; *. The PDP-II NIE restores the
contents from its internally saved table.
Example:
NIE> (A) ? UNS

SHOW COUNTERS

Types the contents of the host node DEUNA (Digital ETHERNET-toUNIBUS Adapter) internal counters. The counters are described in the
DEUNA User's Guide (EK-DEUNA-UG).
Example:
NIE> (A) ? SH C

SHOW MESSAGE

Types the current message parameters for size, type, and copies.
Example:
NIE> (A) ? SH M

SHOW NODES

Types the contents of the node table.
Example:
NIE> (A) ? SH N

SUMMARY

This command types the summary table. The NIE maintains the following
information about nodes to which it has sent messages:
RECEIVES NOT COMPLETE
LENGTH ERRORS
BYTES COMPARED

RECEIVES COMPLETE
DATA COMPARE
ERRORS
BYTES TRANSFERRED

BYTES COMPARED represents data minus the loop-server protocol overhead; therefore, it will be less than BYTES TRANSFERRED which represents data plus loop-server protocol overhead.
Example:
NIE> (A) ? SUMM

C-14

EXIT

Returns control to the diagnostic supervisor (either VDS or DRS). The DRS
RESTART and CONTINUE commands cannot be used if the EXIT
command was:
CVNIA HRD ERR 00028 ON UNIT 00 TST 001 SUB 000 PC:63730
TIMEOUT OCCURRED BEFORE LOOPBACK REPLY
FAILING NODE ADDRESS: AA-00-03-00-00-00
DATA PATTERN: ONES

C.S.2 Other Error Messages
Error Message

Description

?ILL CMD-BAD SYNTAX

A command with an illegal character was typed; retype the
command.

?INCOMPLETE

A required part of a command was omitted.

?NUMBER TOO BIG

The numeric string value in the command line was larger than 65535
(177777 octal).

?BAD RADIX

An 8 or 9 was typed when an octal string was expected.

C-15

Digital Equipment Corporation