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Document:	DZ11 User's Manual
Order Number:	EK-DZ110-OP
Revision:	PR1
Pages:	92
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OCR Text

DZ11
user’'s manual

dlifglit[al1

EK-DZ110-OP-PR1

Dz11
user's manual

digital equipment corporation - maynard, massachusetts

Preliminary Edition, March 1977

Revised Preliminary Edition, June 1977

Copyright © 1977 by Digital Equipment Corporation
The material in this manual is for informational
purposes and is subject to change without notice.
Digital Equipment Corporation assumes no respon-

sibility for any errors which may appear in this
manual.
Printed in U.S.A.

The following are trademarks of Digital Equipment
Corporation, Maynard, Massachusetts:
DEC

DECtape

DECCOMM

DECUS

DECsystem-10

~ DIGITAL

DECSYSTEM-20

MASSBUS

PDP
RSTS

TYPESET-8
TYPESET-11
UNIBUS

/77-38

CONTENTS

Page

CHAPTER

GENERAL

DESCRIPTION

INTRODUCTION

PHYSICAL

DZ11

DESCRIPTION

Configurations

FUNCTIONAL

1-23

DESCRIPTION

PDP-11

Unibus

Control

Logic

Line

1-13

SPECIFICATIONS

GENERAL

1-23

Interface

1-23

1-25

Interface

INSTALLATION
SCOPE

CONFIGURATION

DIFFERENCES

UNPACKING

INSPECTION

AND

INSTALLATION

CHAPTER

PROCEDURE

PROGRAMMING
INTRODUCTION

Device

and

Control
Receiver

Line

Vector

BIT

and

Address

Assignments

ASSIGNMENTS

Status

Buffer

(CSR)

(RBUF)

Parameter Register

iii

(LPR)

CONTENTS

(Cont)

Page

Transmit
Modem

Control

Status

Transmit

Baud

(TCR)

(MSR)

(TDR)

FEATURES

Length

Bits

Patity
Interrupts

Emptying

the

Silo

Transmitting a Character
Data

Set

Control

PROGRAMMING

EXAMPLES

ILLUSTRATIONS

Figure

No.

Title

1=1

DZ11

System

1-2

DZ11

EIA

Panel
DZ11

Panel

Applications

Module

(H317-E),
20

(M7819),

and

Module

(H317-F)

and

Distribution

Cable

(BCO05W~15)

(M7814),

Cable

3=-15

3-15

Rate

Character
Stop

Data

PROGRAMMING

Distribution

(BC08S-15)

3-16

(Cont)

ILLUSTRATIONS

Figure

Title

No.

Interconnections

Hardware

DZ11

Turnaround

H327

H3271

H3190

Staggered

Test

Connectors,

Turnaround

Line

H327

and

H325

General Functional Block Diagrém
M7819

Address

M7819

Vector

Selection

Interconnection

BCO5W-15

M7814 Address Selection
M7814

Vector
Bit

Selection
Assignments

TABLES

Table

Title

No.

Configurations

DZ11

Model

DZ11

Performance

Items

Supplied

CSR

RBUF

Bit

Parameters

Per

Configuration

Functions

Bit

3-11

Functions

LPR Bit Functions
Baud

Rate

Selection

3-13

Chart

3-18

CHAPTER

GENERAL

1.1

DESCRIPTION

INTRODUCTION

The D711 is an asynchronous multiplexer that provides an interface
between a PDP-11 processor and eight (8) asynchronous serial lines.

It can be used with PDP-11 systems in a varilety of applications
that include communications processing, time sharing, transaction

processing and real time processing. Local operation to terminals
or computers is possible at speeds up to 9600 baud using either
ETIA RS232C interfaces or 20 mA current loop signaling. Remote

operation using the public switched telephone network is possible

et
with DZ11 models offering EIA RS232C interfaces. Enough data-s

control is provided to permit dial up (auto answer) operation with
modems capable of full duplex* operation such as the Bell models
103 or 113 or equivalent. Remote operation over private lines for full

duplex* point to point or full duplex* multipoint as a control (master)
station is also possible. Figure 1-1 depilcts several of the possible
applications for the DZ11

1n a PDP-11

system.

*The DZ11 data-set control does not support half duplex operations
or the secondary transmit and receive operations available with
some modems such as the Bell model 202,

etc.

The

DZ11

has

parameters
bits

for

several

such as

each

features

baud

line,

data

set

control,

detection,

silo

SPC

slots,

and

Each

DZ11

module

serial

lines.

sixteen

used

with

(EIA

This

fact

line

the

length,
for

baud

rate,

received

control

number of

each

Additional

for

line,

features
break

data,

operation

module

stop

and
include

generation

module

Also

system

panel,

note

consists

interfaces

distribution

panel.

parity

flexible

plug-in

limited
and

hex

turnaround.

output)

allows

provides

line

even

receiver

buffering

one

provide

character

interrupts.

zero

Since

(16)

rate,

odd

transmitter-receiver

that

mix

eight

two

the

EIA

and

these

(2)

two

different

(8)

channels

DZ11

with

modules

versions

module

asynchronous

and

can

the

panel

using

DZ11

types.

multiple

DZ11s.

1.2

PHYSICAL

The

DZ11

and

(8-line

5.25-inch,

ribbon

the

DESCRIPTION

cable.

configuration)
unpowered

Several

distribution

panel

comprises

distribution

types

and

the

single

panel,

interconnecting

modem

hex

SPC

connected

cables

terminal,

module

are

15-foot

used

depending

between

the

device. A 16-1line configuration uses two modules and a single
distribution
cables,

The

and

panel

connected

distribution

subsequent

paragraphs

panel

two
are

present

ribbon
shown

cables.

detailed

Figures

The

DZ11

1-2

description

modules,

and

1-3.

the

physical and electricél specifications of the various DZ11 options
and

configurations.

LOCAL

|
DATASET

REMOTE

TELEPHONE

7~ LINE

--——— 4+ — — — — — — DATA SET

REMOTE
TERMINAL

|
U

DZ11

SYSTEM

|
I

DATA SET

—

LOCAL

TELEPHONE

DATA SET

[‘f

TERMINAL

8 TER-

—>b

MINALS

| a—p

MODEMS { <

DZ11

SYSTEM

LBJ
S

i
I

PDP-11
COMPUTER

11-4332

Figure

1-1

DZ11

System

Applications

SRR

‘(d-LLEH)

£-80¢8

2UOT3INAaTInIbTStTgA€T-P12Uu®ed (A-LEH)¢pue=T1T9edD(S1-5S804d)
Whos Avax

Q¢ VYW STNPOW ‘(P18LW)

1=5

1.2.1

The

DZ11

can

designated
and

the

The

DZ11-E

and

the

supplied

DZ11-B
is

suffix
options

the

DZ11-D

combination
option

Configurations

are

The

DZ11-B

slot

different

letter

(A,

are

devices

a DZ11-C

configurations

and

six

EIA

combination

configurations

DZ11~A

loop

and

shown

and

versions.

Table

The

1-1

DZ11-A
control.

The

DZ11-F

shows

hardware

each

modem

DZ11-B.

The

for

1is

the

DZ11-C

the

various

1-4.

an M7819 module

any

F).

with partial

required

Figure

DZ11-A

DZ11-D.

each use

DD11-B,

output

the

configurations,

system unit

that plugs

with

into

hex SPC

slot;

howevef, slots in the PDP-11/20 BA11 box cannot be used. The H317-E
distribution

modules

DZ11-E

panel

lines

provides

per

module),

configurations.

lines

for

M7814

the

The

and

modules

(20

system).

power

and

Modems

can

DZ11-F

mounted

terminals

are

and

H317-F

DZ11-C
mA

communication

included

from

two

with

the

DZ11-A

distribution panel

configurations,

The

lines

connected

provides

which

use

distribution panels

H960

19-inch

the

M7819

and

the

require

cabinet.

H317-E,

the

EIA

panel,

cables'that attach to its 16 DB25P cinch connectors. These cables
are not provided by the DZ11
by

the

customer.

interconnections,

terminal

cable

The

BC05D-25

and

the

interconnections.

connects

from

carries

the

data

between

terminals

the

and
and

and therefore must be bought separately
cable

BCO3M

cable

the

BCO05W-15,

M7819 module

control

recommended

signals

H317-F,

the
1-6

for

recommended

50-conductor

for

flat

the

EIA panel.

all

lines.

mA panel,

data

set

local

shielded

This

conductor

Connections

are

customer

Table

1-1

DZ11

Model

Configurations

Model

Output

Module

Panel

Connector

Cable

DZ11-A

EIA

M7819

H317-E

H325/*%*H327

BCO5SW

DzZ11-B

EIA

M7819

**H327

BCO5W

DZ11-E

EIA

*M7819

H317-E

H325/*%**H327

*BCO5S5W

DZ11-C

M7814

H317-F

***H3190

BC08S

DZ11-D

M7814

***H3190

BCO08S

DZ11~-F

*M7814

****H3190

*BCO08S

*=qguantity

**=H327

will

- -

H317-F

two

replaced

H3271

later

models.

Check

shipping

list to see if there is one.
***=Not

supplied

there

one.

with

early

models.

Check

shipping

list

see

supplied

cables

its

control

signals

all

BC08S-15

Two

accessory

each

DZ11-A.

panel

signals

test
The

end

onto

single

and

staggers

cable
the

are

The

(M7814

shown

using

the

priority

module

Maximum

*This

see

BCO08S

new

H3271

becomes

M7819

module.

shielded

you

interrupts

available.

be
as

are

provided
on

back
to

the

panel

with

distribution

data

the

connected
shown

and

cable.

and

modem

module

one

Figure

also

have

staggered

item

and

the

shipping

one.

plugs

item replacing

loop

connects

can

The

staggers

allows

data

with

H3271)

1-5.

The

1-7.

new

have

and

insert

connector

The

distribution

ribbon

EIA

lines

options
is

the

*H3271

H3271

modem

strips.

and

cable

modules

Figure

This

establish

The

configuration

line.

and

cable,

level

BCO05D

module)

(H3190).

checked

the

terminal

carried

H325

into

M7819

data

connector

flat

plugs

(two

connectors

H325

screw)
are

connectors,

the

BCOS5W

lines

conductor,

the

(four

into
at

H3190

lines

shown

socket

the

The H327

M7819

the

Unibus.

modules

per

Unibus.

plugs

The

H327

may

directly

into

should

the

the H327.

list

the

level

DZ11

connects

turnaround

M7814

Figure

1-6.

M7814

used

until

the

PDP-11

UNIBUS

3¢
DZ11-A

lDZ11-B

M7819

(SPC SLOT)

M7819

( SPC SLOT)

< BCO5W-15 —p
8 LINES

H317-E

AEEEENEN

DZ11-C

M7814

( SPC SLOT)

8 LINES

{e——— LINES —
16

(EIA OUTPUT)

DZ11-D

M7814

(SPC SLOT)

< BCO8S-15 —
-

8 LINES

1 e——— LINES ——

(20mo OUTPUT)

8 LINES

Lt bbb
CABLE

103A OR

DATA

EQU'VALENT

LOCAL

SET

LOCAL

TERM!NAL

TERM“\]AL

TELEPHONE
LINES

NOTE
% Not included with DZ11, must be
ordered separately.
%% DZI1-E=DZ11-A

11-4333

and DZ11-B

DZi1-F= DZ11-C and DZi1-D

Figure

1-4

DZ11

Hardware

1-9

Interconnections

TRANS @

> REC 1

DTR @

CO @

]

RI @

REC @

&> RT

& CO 1

- DTR 1

‘

& TRANS |

NOTE:

Lines 2 & 3, 48;50nd 6 & 7 are

staggered the same way.

11-4334

Figure

1-~5

H3271

1-10

H327

Turnaround

20MA LOOP

AAVAvAf

LINE O
TRANSMITTER

g®

1
LINE

RECEIVER

!
p3

20MA LOOP
—0

LINE 1
TRANSMITTER
[

LINE O

A
A A

$ RECEIVER

A\ A

A A

LINES 2 & 3,4 & 6, AND 6 & 7 ARE STAGGERED THE SAME WAY
11-5141

Figure

1-6

H3190

Staggered
1-11

Line

Turnaround

Figure

1~7

Test

Connectors

H327,
1-12

H3190,

H3271,

and

H325

1.3

GENERAL

The

following

and

performance

Table

1-2

1.3.1

SPECIFICATIONS

paragraphs

contain

specifications

lists

the

electrical,

for

performance

all

DZ11

parameters

environmental,
configurations.

Dz11.

Outputs

1.3.1.1
levels

Dz11-A,
and

INDUSTRIES

-B,

connector

and

pinnings

ASSOCIATION

recommendation

-E

V.24.

that

(EIA)

The

Each

RS232C

supported

101)

provides

conform

standard

leads

(CCITT

line

voltage

ELECTRONIC

and

CCITT

this

option

Protective

are:*

Circuit

Ground

Circuit AB

(CCITT 102)

- Pin 7

Signal Ground

Circuit

(CCITT

103)

Transmitted

Circuit

(CCITT

104)

Received

Circuit

(CCITT

108.2)

Circuit

(CCITT

125)

Circuit

(CCITT

109)

Data

Terminal

Ring

Indicator

Carrier

Protective

Ground

Ready

NOTE

Signal
are

Ground

connected

and

together.

*Circuit CA (CCITT 105, Request to Send, is connected to circuit
cD

(DTR)

the H325

and RI

through a jumper on the distribution panel.
or H315

test

(cirquits CF

connector

and CE).

This allows

turn around DTR into both CO

It also

allows control of

the

Request

to Send (RTS) (CA) line for full duplex‘modem data set applications
that

use

the

202

data

set.
1-13

1.3.1.2

DzZ11-C,

loop

for

used

(for

each

1.3.2

All

passive

operation

line)

and

connection

provided).

drive

-D,

lines

device.
may

order

-F

Each

local

are

active

However,
used

allow

the

line

terminals

(no

current

data

set

control

and,

therefore,

can

pair

receivers

active

passive

convert

DZ11

H319

from

only

drive

active

device.

DZ11s.

The

DZ11-A,

the

DZ11-E

and

-F

Inputs

The

PDP-11

and

Unibus

present

two

1.3.3

Power

one

unit

Typical

the

unit

loads

input

load

the

Requirements,

for

all

the

Unibus

and

Unibus.

DZ11-A,
-B,

and

-E*

Maximum

2.2

2.5

amperes

5.0

volts,

0.13

0.15

amperes

-15.0

volts,

0.1

0.13

amperes

+15.0

volts,

1.3.4

Power

Typical

Requirements,

DZ11-C,

-D,

and

-F*%

Maximum

2.1

2.3

amperes

5.0

volts,

0.4

0.42

amperes

-15.0

volts,

0.12

0.15

amperes

+15.0

volts,

*DZ11<E

and

DZ11~F

are

twice

the

1-14

above

given

values.

1.3.5

Environmental

Class

Requirements

Environment

Operating

all

Dz11s:

5° ¢ to 50° C*

Temperature:

(41° F to 122° F)

Relative

Humidity:

with

less

maximum

of 32° ¢
.

minimum
(36

95%,

wet

(90° F)
:

dewpoint

and a
of

Cooling

pzZz11-A,

~B,

DZ11-E

and

Heat

~-C,

and

-D:

=-F:

Air

flow 3

cu.

feet/min.

Air

flow

cu.

feet/ min.

Dissipation

DZ11-A

and

-B:

Dz11-E:
DZ11-C
DZ11-F:

and

~-D:

Btu/hr

114

Btu/hr

110

BTU/hr

:
:
*Maximum operating temperature 1s reduced 1.8

(1.0O F per 1000 feet)

per

for operation at altitude.
1-15

1000

bulb

meters

1.3.6

The

Distortion

maximum

allowed

The

maximum

for

2000

maximum
2.2%.

DZ11~-A,

mark"

received

speed

baud

speed

All

1.3.7

"space

and

distortion
3.8%.

baud

and

All

from

have

baud

the

space"

distortion

40%.

allowed

other

rates

"mark

character

distortion

other

-B,

received

rates

allow

transmitter

less

than

for

character
4%.

The

2000

baud

2%.

Interrupts
RDONE

Occurs

each

time

character

appears

the

silo

enter

the

output.

Silo

Alarm,

silo.

Rearmed

disables

TRDY

Occurs

occurs

the

when

transmit

after

reading

RDONE

the

characters

the

silo.

This

interrupt

interrupt.

scanner

finds

line

ready

on.
NOTE

There

1.3.7.1

Interrupt

supplied.

The

using

the

are

Level

interface

proper

modem

Normally,

level

priority

1-16

can

plug.

interrupts.

Level

modified

priority

plug

Level

1is

Table

Data

Parameters

DESCRIPTION

PARAMETER

Operating

Performance

DZ11

1-2

Mode:

Format:

Duplex

Full

1-1/2

one start and

serial by bit,

Asynchronous,

level codes only),

stop bits

supplied by the hardware under program control.

Character

Size:

not

Polarities:

Order

may

SIGNAL

High = 0

CONTROL

Low

SIGNAL

High =

Bit,

odd

High =

Low =

selectable.

program

Interface

Unibus

DATA

or 8 bits - program selectable.

(Does

include parity bit.)

Parity

Parity:

Bit

Low

High

may

none,

20 MA Loop

EIA Out

Low =

= MARK

Low

High

0-5 MA
15-20 MA

OFF

Transmission/reception low order bit

1=17

even.

High = 0 = SPACE

Low =

There

first

Table

1-2

DZ11

Performance

PARAMETER

DESCRIPTION

Baud

50,

Rates:

75,

1800,

Breaks:

Can

Throughput:

21,940

110,

2000,

Parameters

134.5,
2400,

generated

150,

3600,

and

300,

600,

1200,

4800,

7200,

and

detected

characters/sec

(Bits/second

(Cont)

No.

each

line.

Lines

direction)

Bits/Character

Example:

(9600

2)=

= See

Example

21,940

characters/sec

NOTE

21,940

Actual

throughput

other

theoretical

factors

system

1«18

such

software,

9600.

etc.

maximum.

dependent

type

CPU,

Line

Speed:

The

baud

and

receiver)

1is

the

receiver

for

each

off

under

turned
Baud

rate

Rates

available

Distance:

pz11-aA,

15
a

meters

line

-E

can

program
for

Also,

individually

control.
list

(See

feet)

cable

selectable.

line

1-2

transmitter

rates).

and

(50

(both

program

Table

baud

-B,

BCO5D

for

9600

baud

with

equivalent.

Operation beyond 50 feet does not conform to
the

RS232C

operation

distance
type

or
will

cable,

can

not

beyond
the

DZ11

speed

specifications.
possible

the
of

operation

absence

noise.

For

these

may

error

free

However,

the

connected

and

electrical

over

long

excessive

Digital

communication
EIA

versions

local

(and

most

other

beyond

feet

with

satisfactory

1-19

equipment,

reasons,

terminals
50

However,

longer

communication

the

feet.

terminal

guarantee
50

Reliable

depends

electrical

V.24

often

depending

environment.

cables

CCITT

terminals

Digital
at

distances

results

the

terminal

same

and

computer

building,

Shielded

twisted

are

located

modern

office

pair

(Belden

8777

the

environment.
or

equivalentf is recommended and is used in the
BCO3M

null

modem

With

cable

made

such

the

following

with

Belden

shielded

8777

rate/distance

guide.

purposes

cable.

This

only

warranty

chart

and

not

Digital

pairs,

equivalent,

table

twisted

for
to

may

the

used

informational

construed

Equipment

Corporation

of error free operation of the DZ11 at these
and

speeds

distances

feet)

under

all

9600

Baud

circumstances.

(300

300

(1000

feet)

4800

Baud

300

(1000

feet)

2400

Baud

900

(3000

feet)

1200

Baud

1500

(5000

feet)

300

Baud

1-20

NOTE

the

between

will

terminal

and

DZ11

two

volts.

generally

limit

exceed

not

difference

potential

ground

The

within

single

power

service.

noisy

electrical
should

requirement

operation

served

building

operation

This

must

one

cases,

environments,

other

used.

The length of cable that may be used reliably
is

function

cable

resistance,

operation.

a guide,

The

noise,

and

speed

type,

following

however,

error-free

electrical

there

chart

operation under

1-21

no
all

1loop
of

given

guarantee

circumstances.

SPEED

(Baud)

Belden

8777,

AWG,

shielded,

twisted

(shields

floating)

DEC

P/N

9600

150

(500

4800

300

(1000

2400

600

(2000

1200 and below

9107723

ft)

pairs

AWG,

inside

DEC

conductor

station

P/N

9105856-4

300

(1000

ft)

f£t)

540

(1800

f£t)

ft)

900

(3000

ft)

1200 m(4000.ft)

1-22

1500 m (5000 ft)

wire

1.4

FUNCTIONAL

The

following

operation.

that

Interface,

The

the

PDP-11

Unibus

Control

Logic

transmit

and

These

DZ11

and

Control

handle
be

The

scanner

based

divided

generates

used

and

components:

the
to

the

from

the

DZ11

diagram

Unibus

from

the

data

the

handles

Control

the

The

address

data

handling

function,

PDP-11

registers
in

necessary

Unibus.

proper

load

address

handling

controls

Logic.

handling,

the

desired

all

data

wvarious

preselected

DZ11

conditioning

activates

and

DZ11

its

voltage

and

its

the

functions:

and

logic

PDP-11

function

locations.

interrupt

The
and

the

to
address

read

Unibus.

route

The

the

interrupt

processing

between

processor.

Logic

all

can

data

initiates

the

block

Interface.

control.
to

provides

outgoing

function

1.4.2
The

and

basic

component

three

recognizes

are

description

functional

Line

Unibus

data

control

signals

control
the

and

when

incoming

the

receive

general

Interface

interrupt

and

three

Interface

routes

general

and

performs

and

Interface

recognition

Logic,

between

recognition,

into

Unibus

present

1is

DZ11

Interface

signals

1-8

Control

transactions

the

paragraphs

Figure

divides

1.4.1

DESCRIPTION

provides

transmitter
into

two

signals

from

that

and

major

continuously

information

the

required

receiver
sections:

examines

the

cause

Line

data

line,
1-23

each

timing

operations.
the
line

Interface

and

flow

control

The

scanner
in

Control

and

the

succession,

and

the

from

signals

registers.
and

registers,

the

Logic

appropriate

PDP-11
INTERFACE

CONTROL

REGISTERS

e |

LINE

INTERFACE

> LINES

|
|

ADDRESS

SCANNER

nwcoHZ2C

DATA

I_..__..____.._______.

contRoL |

11-4335

Figure

1-8

General

Functional

1-24

Block

Diagram

The scanner comprises a 5.068 MHz oscillator (clodk), a 64-word
FIFO

receiver

control

The

generating

DZ11

unique

buffer,

uses

and

six

Device

accessible

discrete

status.

Depending

operation.

Registers

can be

ability

read
to

loaded

four

16-bit word

input

and

the

capacity.

output

data,

operating

registers

are

to word-only

(written),
a

six

depending

allows

the

independent registers.

Interface

important operations

are required

in the DZ11

and parallel-to-serial

(serial data paths).

the DZ11

since

(a parallel data path)

Unibus

other

that yields

restricted

two of the Device Registers

conversions

and

establish DZ11

some
are

others

store

and

functions,

words;

serial-to-parallel

lines

temporarily

write

of the most

from

each having

Line

network,

a manner

read

1.4.3

The

conditioning,

their
or

in bytes

use

registers,

signal

accessible

operation.

clocking

Registers

registers

control

the

four-phase

logic.

four

monitor

Two

and

either

Conversions

data

the conversions
formats.

These

located between the PDP-11

local

for

are

terminals or telephone

each

in the
line.

DZ11

are performed by independent Universal Asynchronous Receiver-Transmitter
integrated circuits.

(UART)
the

Line

DZ11

lines

Receiver or Driver,

Another component of
converts

that they correspond to

(modem

those

terminal).

1=-25

the Line

the TTL voltage
in the

Interface,

levels

external device

in the
input

CHAPTER

INSTALLATION

2.1

SCOPE

,
This chapter contains the procedures for the unpacking, installation
and initial checkout of the DZ11 Asynchronous Multiplexer.

2.2

CONFIGURATION DIFFERENCES

The DZ11 can be supplied with or without a distribution panel. The
D7Z11-B and -D do not have distribution panels. The following list
describes

the variations:

D7Z11-A EIA level conversion with distribution panel (8 lines)
D7Z11-B EIA level conversion without distribution panel (8 lines)

DZ11-C 20 mA loop conversion with distribution panel (8 lines)
)
DZ11-D 20 mA loop conversion without distribution panel (8 lines

2.3

D%Z11-E DZ11-A and Dz11-B

(16 lines)

D7Z11-F DZz11-C and Dz11-D

(16 lines)

UNPACKING AND

INSPECTION

ices.
The DZ11 is packaged in accordance with commercial packaging pract
st
First, remove all packing material and check the equipment again
to the
the shipping list. Damage Or shortages should be reported
shipper immediately, and notification given the DEC representative.
s, loose
Inspect all parts and carefully inspect the module for crack
ins
components, and separations in the etched paths. Table 2-1 conta
a list of supplied items per configuration.

2.4

The

INSTALLATION

following

module

Quantity

paragraphs

PDP-11

Table

Items

install

Supplied

Per

H3271

Test

Connector**

Distribution

Test

Panel

Assembly

Ccable

Printset

(B-TC-DZ11-0-6)

Printset

(B-TC-DZ11-0-10)

Software

Kit

Mounting

Hardware

Insert

User's

Module

BC08S

Cable

Distribution

Set

(EK-DZ11-0P-001)

Panel

(B-TC-DZ11-0-11)

Printset

(B-TC-DZ11-0-12)

Test

contains
An

H327

becomes

two

item:

Assembly

X
X

Connector**=*

will

the
be

available.

Check

items

shipped

Check

listed.
with

each

shipping

M7819

list

unit

see

one.

***New

Printset

H3190

(5)

Manual

BCO5W=-15

H317-F

DZ11

Connector

M7814

item:

DZ11

the

Configuration

Module

Priority

one

followed

M7819

Panel

this

Description

H325

**New

should

system.

2-1

H317~E

*Shipment

PROCEDURE

shipping

list

2=2

see

there

one.

until

there

2.4.1

H317

Install

the

Assembly

Distribution

H317

Panel

Installation

Distribution Panel

Drawing

according

the

Unit

D-UA-DZ11-0-0.

2.4.1.1

EIA Option - For the DZ11-A or DZi1—E option, check

that

ensure

all

Distribution Panel

use

future

data

202

DTR lead

set.

jumper

The

should

feature

Force Busy

and the

in anticipation

other

than

the

103;

The

Jjumper

also

however,

labeled DTR
Request

to assert both DTR and RTS

if using a

connected

the

implement the Force Busy function.

that

normally be

the

are

DTR to pin

connects

labeled BUSY

in Modems

for use

jumper

This

now functional.

the DZ11

This allows

Send.

are

jumpers

These

with modems

DZ11

Jjumpers

See Drawing E-UA-5411928-0-0

locations.

D-CS-5911928-0-1)

(Refer

machine-insertable

in place.

are

the

jumpers

the

two

the

jumper

the Printset for
of

cut

software

out unless

the

the modem has

implemented

control

it.

20 mA Option - For the DZ11-C or DZ11-F option, refer to

2.4.1.2

on the Distribution Panel
Each line has a jumper

D-UA-5411974-0-0.
(W1

through W16)

300

baud or

which

The

less.

should

jumper

the

terminal

should be removed

operates

for higher baud

rates.

2.4.2

M7819

install

Module

Installation

the M7819 module,

Ensure

perform the

following:

that the Priority Insert

(level

1is

properly

seated in socket E52 on the M7819 module(s).

Refer

drawing

D-UA-M7819-0-0.

2-3

Refer

Address

paragraph

3.1.1

Assignments.

Set

for

descriptions

the

switches

the

E81

such

that

the module will respofd to its assigned address. When a
switch

closed

switch

open

the
to

switch
bit

(off),

labeled
etc.

selection

switch

Switch

position

E11.

corresponds

open

opposite

you

step

Insert
connect

bit

corresponds

2-1.

the

eight-position

not

corresponds

vector

bit

When

switch

the

etc.

decoded.
decoded.

switch

new

the

module
flat

address

a
that

are

binary

the

Note

the

decoded.

When

and

binary

otherwise

decoded.

have

position

bit

not

accomplished

Switch

the

corresponds

vector

binary

(on),

(off),

binary

Figure

a
a

See

Vector

closed

(on),

When
Note

H3271

test

switch

that

decoding.

used.

this

See

Figure

connector,

2-2.

following:

(s)

into

shielded

SPC

cable

slot

and

(BCO5W-15)

on the module(s). Connect the other end of

the

cable

the

H3271.%*

CAUTION

Insert

and

remove

carefully

components

modules

slowly

avoid

snagging

the

card

guides.,

module
and

possibly changing switch settings
*The

H3271

has

room

for

two

H7819

cables.

inadvertently.

A11

A T

OFF

A10

NOTE:

Address 160000 - A12 through A3, OFF
160010 - A12 through A4, OFF;
- A12 through A3, ON
177770

MSB |

;

14|

131211

;

|10]|

LSB

7|6

SWITCHES

A3, ON

|4]|

3|2

| x

| X

]

7
2 TO

6 OR 7

(DZ11 REGISTERS)
11-4563

Figure

2-1

M7819

Address

Selection

ON
E11

OFF

NOTE:
_ = OFF

ON = ON

VECTOR

Va4

300

- 310

’

Own

—

'
770

o M

I
11-5314

Figure

2-2

M7819

Vector

Selection

Run

the

verify
the

DZ11

diagnostic

module

operation.

diagnostic

without

Remove

SURE

listing.

staggered

Refer
Run

mode

MAINDEC-11-DZDZA,

least

two

passes

error.

the

J18

BCO05W-15

J20

THAT

cable(s)

the

TWIST

from

the

H3271

H317-E

Distribution

PUT

THE

CABLE.

properly

and

insert

Panel.

See

Figure

2~-3,

Ensure

step

that

the

H327

Test

Connector

(the

cable

connector

Insert

the

M7819

the

staggered

MAINDEC-11-DZDZA,

correct

its

mode

procedure.

SPC

the

slot

verify

the

Run

top

and

least

run

module

diagnostic

two

the

installed

M7819).

diagnostic

operation.

listing
passes

for

Refer

the

without

error.

CAUTION

Insert

and

remove

carefully

components

possibly

modules

avoid

the

card

changing

slowly

snagging
guides,

switch

module
and

settings

inadvertently.

EIA
DISTRIBUTION

PANEL

ES\
BCOSW-15

CABLE

An'a
OUTPUT BOARD

11-4327

Figure

2-3

BCO5W~15

2-5A

Interconnection

Replace the H327 Test Connector with the BCO5W-15
cable,

and observe the same caution as 1n Step f

above.

Insert the other end of the cable at J18 or

J20 of the Distribution panel. BE CERTAIN THAT A
TWIST IS MADE IN THE CABLE.

Connect the H325

See Figure

(or an H315)

2-3.

connector to the first

line and run the Diagnostics in External mode.
for

each

line.

Repeat this

step

Run DEC/X11

System Exerciser to verify the absence

of Unibus interference with other system devices.

The DZ11

is now ready for connection to external

equipment.

If EIA

to a terminal,

(H317-E),

and the connection 1is

a null modem cable must be used. The

BCO3M, H312-A, or BCO3P null modém cables will suffice
for connection between the Distribution panel and

the terminal. However, if the H312-A null modem unit

is used, two BCO5D EIA cables
the null modem unit)

(one on each side of

are required. If connection 1is

to a Bell 103 or equivalent modem, a BCO05D-25 feet

cable is required between the Distribution panel'and
the modem. All of the cables mentioned must be ordered

separately

DZ11
to

2.4.3

terminal

echo

M7814

install

they

shipment.

the

test

Module

the

for

that

seated

socket

Set

switch

closed

switch

open

bit

then

standard

the

supplied

connection
cable.

and

EIA

perform

the

following:

etc.

3.1.1

without

E81

the

Run

error.

module(s).

binary

such

address

that

address.

properly

When

decoded.

decoded.
to

the

eight-position

When

switch

decoded.

When

binary

decoded.

Note

that

the

When

bit

switch

decoding.

this
Also

switch

closed

(on),

open

(off),

the

note,

opposite

that

switch

and

are

not

used

and

switch

bit

etc.

Refer

Figure

2-5.

Note

positions

bit

2-4.

binary

switch

D-UA-M7814-0-0.

corresponds

address

E72

assigned

description

binary

Figure

(level

drawing

for‘a

its

labeled

selection

switches

(on),

See

insert

Refer

(off),

Vector
on

the

respond

switch

customer

E41.

paragraph

will

priority

module

the

(H317-F),

both

the

assignments.

that

components

Module,

Ensure

NOT

Installation

M7814

Refer

are

corresponds

A1l

A10

OFF

NOTE:

Address 160000 - A12 through A3,

OFF
160010 - A12 through A4, OFF;
177770
- A12 through A3, ON

A3, ON

MSB

LSB

12 | 11

SWITCHES

3
e

)

]

6 OR 7

©@ TO 7

(DZ11 REGISTERS)
11-4562

Figure

2-4

M7814

Address

Selection

OFF

E81

NOTE:
OFF

ON = ON

300

- ON

310

VECTOR

770
11-5140

2-5

M7814

Vector

Selection

CAUTION

Insert

and

carefully

remove
to

components
possibly

modules

avoid

the

snagging

card

changing

slowly

module

guides,

switch

and

settings

inadvertently.

Connect
Insert

Skip

the

module(s)

this

step

otherwise
1.

cable

into

their

you

have

the

DZ11

SPC

slot(s).

test

connector

cable

distribution

panel

(H317-F).

other

Run

assigned

BC08S

the

module(s).

the

Connect

the

following:

H3190

the

BC08S

end

diagnostic

internal

(Maintenance)

mode for two efror free passes. Refer to
MAINDEC-11-DZDZA,
the

Connect
test

Run

proper

step

the

diagnostic

listing,

for

procedure.

1i.

other

end

the

BC08S

cable

the

H3190

connector.

the

error

DZ11

free

diagnostic

passes.

Refer

listing,

for

the

staggered

for

two

MAINDEC-11-DZDZA,

the

correct

mode

procedure.

Remove

the

and plug

BC08S

cable

into J1

from

or J2

the

H3190

test

connector

on the distribution panel

(H317-F)
.

Run

the

absence

DEC/X11
of

system

exerciser

unibus

interference

now

for

with

verify

the

other

system

devices.

The

DZ11

equipment.

supplied
echo

This

cable.

test

ready

accomplished

When

each

connection

hookup

line

without

with

complete
any

external

customer

run

errors

the

occuring.

NOTE

For

only

customer

terminals

transmit

direction,

the

that

receive

echo

test

in
can

can

single
not

run.

CHAPTER

PROGRAMMING

3.1

INTRODUCTION

This

chapter

DZ11.

provides

description

basic

each

programming

constraints,

programming

and

are

also

3.1.1
The

DZ11's

floating

and

device

vector

this

Vector
and

and

programming

its

format,

bit

functions

are

presented

efforts.

Special

programming

the

aid

features

chapter.

Address

vector

device

for

DZ11

and

maintenance

presented

Device

information

Assignments

addresses

address

are

selected

from

the

space.

NOTE

The

Its

floating

DUP11;

Its

LK11;

floating

address

163776 g

The

160010, 3

address

space

address

space

follows

and

floating

device

vector

space

follows

DN11;

DM11-BB

and

DR11-C;

PA611

reader,

PA611

GT40;

vector

the

floating

7768.

DJ11;

DH11;

DQ11;

DU11;

DMC11.

DM11-A;

‘DH11;

3008

space

LPS11;

DQ11;

other

the

modem

punch;

KW11-W;

3-1

DC11;

control

DT11;

DU11;

KL11/DL11-A,

DX11;

DUP11;

vectors;
DL11-C,
DV11;

DP11;

DR11-2A:
D,

LK11-A;

DJ11;
DWUN;

and

DMC11.

above

listed

DZ11

is installed in a system with any of the

options,

then its assigned vector and device address

should follow the vector and device address of the other options.

Two examples

follow:

First, the simplest case where there is only one DZ11:
Vector

Comment

Option

Address

GAP

160010

DJ11s

GAP

160020

DH11s

GAP

160030

DQ11s

GAP

160040

DU11s

GAP

160050

DUP11s

GAP

160060

LK11sV

GAP

160070

DMC11s

DzZ11

160100

GAP

160110

300

DZ11s

system

two

DZ11s.

Next,

and

with

one

DJ11,

one

DH11,

one

Option

Address

Vector

DJ11

160010

300

GAP

160020

GAP

160030

DH11

GT40,

KW11-W

Comment

DJ11s

must

address
a
DH11

one

start

boundary

multiple

that

20.

160040

160050
GAP

160060

320

GT40

DH11s

address

not

the

fldating address space.
330

KW11-W

address

floating

address

GAP

160070

DQ11s

GAP

160100

DU11s

GAP

160110

No DfiP11s

GAP

160120

LK11s

GAP

160130

DMC11s

Dz11

160140

340

Dz11

160150

350

GAP

160160

DZ11s

not

space.

the

3.2
A

comprehensive

shown

and

Figure

DR6)

are

and

instructions
be

The

that

and

DR2

but

either

with

and

DR4

operations,

not

affected

bits

appear

Specific

the

presented

following

3.2.1

Control

The

control

and

enable

bits

have

Status

status
for

each

DR6.

DR6

word

DR2

read

only

cycle

word

constraints.

all

read-only

write-only

each

bus

processor

used

bits

and

are

"not-used"”

performed.

description

each

are

discussed

bit

function

3-3.

scanning,

(DATIP)

reading

operation

for

through

and

the

may

applies:

write,

read-only

PDP-11

instructions

DR4,

This

Since

permits

DR2,

assigning

registers,

programming

(DRO,

two

Also,

paragraphs.

and

assignments

registers.

read-modify-write

3-1

unique

and

constraints

Tables

bit

registers

DR2

following

attempt

binary

six

accesses

byte

the

programming

instructions,
DRO

form

DR6

device

status

perform

with

all

four

(WO)

DR2

used

DR6.

accomplished

write-only

writing

cannot

3-1.

subdivided

subdivision

(RO)

pictorial

(CSR)

contains

processor

the

states

interrupts,

clearing

flags
and

maintenance. The 16-bit CSR has no programming constraints. The
format

Table

Unibus,

depicted

3-1.
and

Figure

Write-only

read-only

and

bits

3-1,

and

bit

"not-used"

are

not

functions

bits

affected

read
by

write

are

described

zeros

attempts.

the

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Table
Bit

Title

0-2

Not

MAINT

CSR

3-1

Bit

Function

Used

read/write

serial
to

CLR

(clear)

fed

receiver.

Bit

read/write

generate

Enable

the

INT

Enable

lines

15-microsecond

CLR

progress

Silo.

reset

are
of

the

Receiver

Cleared

CSR

affected,

RBUF.

enable

that

CLR

not

activates

bit

and

again.

that

CLR

the

set

indicated

which

UARTs,

issued,

registers

around.

one-shot

all

CLR.

bit

read/write

interrupt.

must

through

read/write
to

CLR

data

turned

fires

parameters

are

that

line

input

silo,

the

transmitter

and

bits

the

INIT

receiver

control

causes

BUS

After

and

RCV

All

CSR.

scanner

serial

the

nor

Scan

bit
a

set,

from

cleared

when

data

back

the

Modem

Master

bit,

output

clears

Functions

and

the
Transmitter

BUS

INIT.

enables

the

receiver

CLR

BUS

INIT.

and

Table

Bit

CSR

Bit

Functions

Title

Function

RDONE

read

only

generates
bit

RBUF

reaches
If

bit

flag
a

Line#

the

output

When

bit

bits

indicate

but

when

the
can

that'the
12

another

silo

silo
1,

word

(RBUF).

used

contains

RDONE

these

three

the

line

that

sets

new

within

minimum

08-10

bit

again

line

does

1.9

(TRDY)

ready

clears

the

another
could

to
when

transmit

line

are
is

appear

microseconds.

line

bits

read-only
is

into

number

These
15

Bit

loaded

return

INIT.

when

the

ready.

only

when

character.

character

BUS

clears

ianterrupts but otherwise acts

same.

1 and

bit

that

06 =

RDONE

the

bits

Used

set)

if bit

resets

indicate

buffer,

Not

bit

and

transmit

The

character.

the

(hardware

read

not cause

Tran

bit

a RCV INT

(Cont)

after

CLR

meaningful
true.

The

Table
Bit

Title

SAE

(Silo

3-1

CSR

Bit

Functions

(Cont)

Function

Alarm

read/write

alarm

Enable)

allows

06
The

cause

entries

the

(bit

bit

the
is

causing

from

13)

the

silo

the

bit

after

enables

RDONE

interrupt

flag.

that

and prevents

interrupts.

SAE

bit

can

cleared

be
by

silo.

used
CLR

and

a
BUS

INIT.

(Silo

Alarm)

after

causes

set

bit

read-only

characters

interrupt

hardware

the

enter

the

bit

cleared

CLR,

BUS

INIT,

the

RBUF.

When

the

silo

flag

(sA

the

silo

must

1),

because
until

the

flag

will

additional

not

silo.

and

reading

occurs

emptied
be

set

characters

again

enter

the

silo.

TIE

(Tran

Int

Enab)

A
if

read/write
bit

bit
1

that

(TRAN

allows

Ready)
.

interrupt

Table
Bit

Title

TRDY

3.2.2

The

(Tran

receiver

with

flag.

Ready)

line

one

the

constraints

Buffer

buffer

Functions

two

line

(Cont)

read

The

which

are:

TST

the

loss

The

"Read

BIT

set.

and

found

hardware

when

that

its

has

empty

and

its

LINE

ENAB

cleared

CLR,

BUS

INIT,

the

TBUF

(RBUF)

RBUF

contains

error

DR2

cannot

Only"

the

status,
(RBUF

has

received

character

and data wvalidity

and

performed

LPR),

(write

several

RBUF

1is

operation

programming

used.

instructions

set

bit

instructions

number

buffer

operation

LPR).

bit

transmit

registers

Byte

read-only

identification,

Bit

(RBUF)

accessed when

accesses

CSR

Function

Receiver

bits,

3-1

cannot

used

they

cause

character.

requires master

order

scan

functional.

Enable
When

(CSR bit

this

bit

off,

bits 00 to 14 of the RBUF become invalid regardless of
the

state

bit

(DATA VALID)

and

the

silo

held

empty.

The

Figure

3-1

and

Each

reading

presents

through

the

however,

Bit 15
in

3.2.3

line

the

parameters

and

receiver

functions

the

RBUF

not

become

RBUF

are

zero

Table

3-2.

advances

the

silo

and

the

and

depicted

after

invalid

described

character

(Data Valid)

program.

Bits

BUS

INIT;

the

CLR

silo

emptied.

does clear to zero and is expiained

3-2.

Parameter

The

parameter

they

Table

Line

bit

format

parameter

(character

clock)

for
Line

(LPR)

and

each

16-bit

stop

code

lengths,

line.

Bits

00-02

parameters

for

each

parity,

select

line

that

must

the
be

sets

speed,
line

for

reloaded

after é CLR (bit 04 of CSR) or BUS INIT operation. The programming
constraints

for

BIS

Byte

the
a

LPR

write
BIC

are:
only

instructions

operations

cannot

3-10

are

not

used.

allowed.

Table
Bit

8-10

Line

Bit

Functions

Function

Title

RCV

RBUF

3-2

Character

Number

These

bits

the

bits

contain

selected

wide,

the

code

level

These

bits

present

which

the

character

character.

less

than

are

bits

order

high

forced

received

zero.

the

number

line

received.

was

Used

Not

Parity

Error

This

had

bit

indicates

bit

a parity

generated

the

whether

The

error.

and

hardware

received

bit

parity
does

not

appear in the RBUF word.

Framing

Overrun

Error

This

indicates

bit

a mark)

bit

not

and

can be

This

bit

used

character

which

character

character,

buffer

received

replaced by
before

(stop

detection.

receiver
is

framing

received

break

result

The

3-11

the

for

indicates

overflow.

received

improper

another

storage

the

Table

Bit

Title

3-2

RBUF

Bit

Functions

(Cont)

Function

silo.

character

received

lost

character

put

indicates

that

but

the

silo

valid.

Data

Valid

This

bit

read

from

The

RBUF

the
is

silo

read

the

(RBUF)

until

the

character

is
DV

valid.
bit

indicating an invalid character and
empty
BUS

silo.

INIT.

3=-12

Bit

cleared

CLR

and

Table

3-3

Functions

LPR Bit

Bit

Title

Function

0=-2

Line Number

These bits select the line for
parameter

3-4

Character Length

Stop Code

set the character length

These bits
for

the

selected

not part

The parity bit

line.

the

character

bits

length.

This bit sets the Stop Code length.
stop,

= One-unit

1.5-unit stop

if a

= Two-unit

5-level

stop

code

employed.)

Parity

This bit selects the parity option
(0 = No parity check,
on

O0dd Parity

TRAN

and

= Parity enabled

RCV.)

This bit selects the kind of parity
selected

= Even Parity

Select,

Table

Bit

8-11

3-3

Title

Speed

LPR

Bit

Functions

Function

Select

Odd

Parity

set

for

RCVR

Select.)

this

bit

bits

speed

for

the

line

0-2.

Refer

Table

This

bit

select

baud

must

parameters

set

and

RCV

bits

for

when

activate

CLR

clock

effect.

TRAN

3-4

list

rates.

on.)

recelver

must

selected

(Transmitter

have

the

clock.

Bit

These

available

(Cont)

BUS

clock

INIT

off.

the

loading
receiver

turns

always

the

3.2.4

Transmit

The

Transmit

the

EIA

option

(M7814
(DTR)

TCR

the

have

The

modem

high

line.

high

byte

have

bit

for

byte

each

not

The

control
the

high
mA

bits

for

that

the

Data

(bits

byte

options

BUS

because

for

the

Terminal

through

15)

they

not

for

each

Read/Write
DTR bit

INIT

only),

only,

not

CLR.

reads

back

into

low

contains

byte

set

bit

allows

explains

CLR

and

options

capabilities.

When

how

BUS

contains

to write

Status

The

(16)

(8)

attempts

bit

the

(M7814

3.3.7

only)

used

line.

Modem

the

cleared

Also,

cleared

eight

difference
up

sixteen

capabilities.

(M7819

Paragraph

module).

and

make

used

control

byte

The

(TCR)

contains

module)

that

not

effect.

3.2.5

This

are

zeros.

all

(M7819

lines

module).

byte

This

line.

Control

options

Ready

Control

it,

Read/Write

properly

the

Unibus

will

transmission
to

When

Line

use

Enable

the corresponding
this

bit.

This

INIT.

(MSR)

used

only

(M7814
not

with

the

EIA

options

module)

not

have

used,

this

(M7819

modem

reads

all

zeroes

Unibus.

The

MSR

consists

and

the

high

each

byte

line's

two

(bits

Ring

bytes:

The

08-15).

Indicator

The

(RI)

low byte
low

byte

lead;

the

(bits

through

monitors

high

byte

the

07)

state

monitors

the

state

Read

only

each

portion

line's

carrier

(CO)

and

the

DR6

has

lead.

The

following

MSR

the

Programming

characteristics:

It's

Read

only

CLR

and

BUS

INIT

have

Bit

format

3.2.6

Transmit

Data

The

consists

TDR

Buffer
The
an

high

byte

individual

with

The

(TBUF)

that

TDR

bit

and
is

When

the

BIS

For

character

only

BIC

Figure

bytes.

The

character
register

BREAK

bit

only

low

that

with
is

zeroes

Write

3-1.

(TDR)
byte

each

set,

the

line

immediately

portion

the

Transmit

transmitted.
controlled

line

associated

and

continuously.

DR6

and

has

the

character

instructions

into

the

hardware

The

BREAK

lengths

the

TBUF

forces

Maintenance

effect.

characteristics:

loaded

the

sending

Programming
Write

8-bit

BREAK

starts

following

holds

bit.

two

the

shown

mode

cannot

less
must

the

has

(i.e.

3-16

than
be

most

used.

8-bits,

right

justified

significant

effect

CRS

bit

when

1).

because

bits

zero.

running

the

3.3

Cleared

Bit

format

PROGRAMMING

The

DZ11

has

baud

rate,

This

section

CLR

and

BUS

INIT.

shown

Figure

FEATURES

several

programming

character

length,

discusses

achieve

the

desired

3.3.1

Baud

Rate

the

features

stop

allow

parity,

and

parameters.

transmission

the

desired

controlled

the

conditions

required

bit

operating

that

operating

selection

3-4

bits,

application

The

Table

3-1.

depicts

the

speed.

Also,

the

baud

bits

these

and

for

controls

through

each

for

line

interrupts.

reception

configuration

rate

control

speed

the

LPR.

each

the

same

for

both the tiansmitter and receiver. Furthermore, the receiver
and

selected

off

setting

line.

the

for

turned

LPR

clock

and

clearing

bit

the

Table

3-4

Baud

Rate

Selection

Chart

Bits

3.3.2

The

Character

selection

controlled

bits

and

level),

Baud

150

300

600

1200

1800

2000

2400

3600

4800

7200

9600

Not

the

four

Rate

Used

Length

one

bits

03,

and

respectively,

level),

available
the

are

and

LPR.

character

The

bit

follows:

level).

For

lengths

conditions

level),

character

is
for

lengths

3.3.3

Stop

The

length

and

the

high

order

serial

length

the

stop,

unless

zero)

3.3.4

The

are

forced

zero.

Bits
stop

bits

determined by bit 05 of the LPR.
stop

bits

one

the

unit;

bit

5-level

selected,

then

set

stop

string

If bit 05 is a zero,

character

the

character

one

length

selects

(bits

bit

length

bit

1.5

the

LPR.

the
a

two-unit

and

units.

Parity

parity

enabled

option

selected

transmission

and

reception

setting

Parity

bit

one.

Bit 07 of the LPR allows selection of even or odd parity, and'bit
06

must

generated
RBUF

the

and

received

The

07
by

significant.

hardware,

parity

error

had

(bit

parity

and

does

12,

The
not

RBUF)

parity
appear

flag

bit

the

set

when

Enable

(SAE)

error.

Interrupts

the

receiver

RIE

PDP-11

check

bit

character

Receiver

bits

for

checked

TBUF.

3.3.5

set

Interrupt

CSR

control

interrupts

and

SAE

are

processor.

for

the

Enable

the

(RIE)

and

Silo

circumstances

the

PDP-11

processor.

both

clear,

the

this

availability

case,

the

data

3=-19

DZ11

upon

never

program

Alarm

the

which

interrupts

must

SILO

the

DZ11

the

periodically

and

empty

the

SILO

when

data

should

time

cover

the

RIE

takes

bit

BIT

the

indicating

for

the

SILO

program

operates

the

SILO

fill,

delays

CSR will

and

When

RDONE

least

time

set when

off

allowing
to

clock

often

safety

empty

character

can periodically

instruction.

factor

the

silo.

available

check

this

the

program

should

interrupt

the

PDP-1

set,

the

SILO.

set

bit

with

SILO.

set

and

the

interrupt

dismisses

the

character

SAE

1is

DZ11

presence
service

MOV

clear,

receiver
of

instruction

interrupt,
available

were

placed

serviced).

Alternately,

interrupt

the

vector

can

from

address

the

may

SILO

when

the
the

RBUF.

RDONE

bottom

character

the

program

then

interrupt when another

immediately

while

interrupt

emptying

will

(which

the

will

obtain

the DZ11

the

DZ11

character

routine

characters

the

program
in

response

the

The

performing

the

characters

processor

The

for

SILO.

empty

RDONE

TSTB

present.

check

the

The

the

additional

interrupt

service

was

routine may

the

SILO

before

dismissing

the

DZ11

will

interrupt

vector

when

the

being
respond

the

interrupt.

RIE

and

processor

bit

the

characters

SAE
to

are

the

CSR
have

both

DZ11

receiver

set.

been

set,

The

placed

bit
the

will
silo

set

since

SILO

when
the

the

PDP-11

ALARM

(SA)

sixteen
last

time

the

program has accessed fhe.RBUF. Accessing the RBUF will clear the
SA

bit

and

the

associated

counter.

The

program

should

the

procedure

described

completely

ensure

that

emptied

are

response

any

Paragraph

3.3.6

silo

alarm

interrupt.

placed

characters

processed

the

empty

silo

the

silo

This

while

will

being

program.

NOTE

the

program

entries
alarm

response

interrupt,

while

will

counted

only

each

are

build

the

silo

characters

interrupts

processed

being

processes

coming

being
without

silo

alarm

circuit and thé silo may eventually
overflow

without

the

alarm

being

issued.

the

silo

interrupted

respond

the

PDP-11

period

will

characters.

alarm

interrupt

fewer

short

program

than

messages

used,

the

characters

during

periodically

depend

required

While

the

program

are

periods

should
the

program

will

received.

empty

the

order

moderate

silo.

responsiveness

emptying

not

silo

activity

The

scanning

received
should

ensure

that DZ11 receiver interrupts are inhibited. This should be done
by

raising

feature

can

required

exit

the

PDP-11

processor

significantly

the

DZ11

interrupt

reduce

receiver

service

priority.

routine

the

The

PDP-11

time

alarm

processor

eliminating

each

silo

the

need

interrupt

overhead

character

enter

and

received.

The

interrupts

vector when

the

indicating

that

the DZ11

processor

interrupt the PDP-11

Transmitter

Ready

(TRDY)

ready

the DZ11

controls

transmitter

interrupt

transmitter
the

bit

accept a

will

the DZ11

enabled,

processor.

the PDP-11

(TIE)

interrupt enable bit

transmitter

set,

CSR

to be

character

transmitted.

the

Silo

empty

the

Emptying

3.3.6

The program can
instructions

the

indicates

zero value

following

entry

the

bottom character.

next character
1

microsecond.

that

to move

Furthermore,

in the

the SILO,

allowing

subsequent

MOV

emptied

the

it has

each word moved out of

the

emptied.

The

SILO has been

the

instruction.

RBUF because

SILO

in the

conveniently by branching on the condition

each MOV

must not access
next

access

for

down

DATA VALID bit

test can be performed
code

move

The program can determine when

SILO by testing
A

character

MOV

Each

storage.

temporary

clear out the bottom of

lost and will

instruction.

RBUF.

RBUF

copy the bottom character

instruction will

won't be

the

from

SILO by repeatedly performing MOV

silo will

Therefore,

A TST or BIT

these

instructions will

down without

following

not be

instruction

saving

current

a MOV from the

RBUF,

least

available

fast CPU's,

the

for

the

cause

the

the program must use

sufficient instructions or NOPs to ensure that successive MOVs

from the RBUF are

separated by a minimum of

microsecond.

will prevent a false indication of an empty silo.

This

3.3.7
The
on

Transmitting

program
the

controls

Unibus:

Parameter

Buffer

the

(TBUF)

and

DZ11

Character

the

DZ11

Control

Following

(LPR),

the

transmitter

and
the

Break

Status
Line

Enable

initialization,

through

the

five

(CSR),

registers
the

Line

the

Transmitter

the

LPR

(BRK).

program

must

use

to spécify the speed and character format for each line to be
used

The

and

must

program

the

CSR

interrupt

The
on

Line
each

set

the

should

Master

the

Transmitter

wants

the

DZ11

Enable
line.

One

bit

The

program

BIS,

BISB,

BIC

and

used,

the

Line

are

DZ11

looking
empty

transmitter

UART

(TLINE)
PDP-11

the

number

processor

bit

TBUF

by
by

the
if

moving
clearing

bit

and

clear

set

the

Enable

CSR.

(TIE)

bit

operate

program

and

disable

transmission

line

(Line

buffer.

the

bits

(If

the

word

DTR

associated

using

MOV,

MOVB,

instructions

registers

with

are

M7819

agcessed.)

line

and
TIE

bit

Line

scanner

Enable

When

the

into

sets

character
the

and

controlled

CSR
the

enable

instructions.

enabled

eight

transmitter

field

TRDY

bit

Interrupt

transmitter

used

this

can

BICB

Enable

simultaneously

for

loads

(MSE)

basis.

line.

The

Enable

set

each

modules

Scan

the

set.

for

the

set)

which

finds

3-bit

Transmit

The

bit,

constantly

has

such

an
a

Line

interrupting

program

indicated

bit.

scanner

TRDY

Enable

bit

which

can

line

Number

the

clear

into

the

Clearing

the

for

lines

initiate

set

the

on
of

should

then

using

line

for

that

line,

line

load

MOVB

the

into

the

character

and

into

wait

resume

setting

and

the
the

the

for

TLINE

character

let

line,

starting

and

idle

indicated

instruction.

the main program

scanner

its

program

should

service.

bit

convenient way

load

the

frees

transmission

the

number

bit

needing

TCR

service

TRDY

the

scanner

scanner
TRDY.

loading
The

transmitted

into

are

to be

line

set

the

normal

request

the

program

interrupts
is

the

TBUF

used,

TCR bit

transmitter

interrupt routine

line

TBUF.

NOTE

The

scanner

needing

may

service

being

started

other

lines

scanner
The

before

request

service

the

program

must

always

the

ensure

services

lines

the

before

being

check

the

TLINE
to

for

TRDY

the

program

requested

eventually
several

the

started.

responding

the

line

occur

characters

Assuming

will

started.

line

when

loads

line.

scanner

being

CSR

finds

will

This

up.

find

correct

the

different

can

field

find

the

find

lines

scanner,

the

line

require

NOTE (Cont)
service,
in

priority

and

continue

order

will

request

determined

line

lowest.

line,

the

program

transmitted

into

the

line

for

service

priority

highest

the

has

the

service

requests

scanner

line

transmission

character

scanner

Line

number.

the

TBUF

should
each

load

time

the

TLINE

and

loads

the

last

request

indicated by

TRDY.

terminate

character

transmission

normally

and

additional

character

Enable

The

normal

line

bit

rest

the

continuous

use

program

despite

the

line

MOVB

the

Break

with
as

load

that

line.

bit

continuous

access
for

will

characters

zero

The

can

sending

lead

any

this

eight

bit

remain

will
The

the

BRK

line

apply

program

normal

transmitted

state.

for

used

set.

Line

line

appear

the

TBUF.

Data

bit

remains

clears

the

(BRK)

One

line.

characters

operation
no

Transmitted

each

the

program

the

program

scanner

The

the

instruction

transmitter
fact

the

line.

instead

signal

long

line,

for

the

The

associated

continues

bit,

for

condition

zero

waits

time

state.

condition

should

break

this

The

setting
the

the
the

program

while

program may

the

use

this

setting
a

facility

the

break

for

sending

bit

and

precisely

using

timed

Transmit

zero

Ready

signals

interrupts

timer.

should

buffered.

remembered

The

program

two

data

The

program

the

characters

end

must
of

additional

data

this.

the

When

load

all-zero

the
At

second
the

end

ensure

zero

loaded

time,
of

preceding

the

zero

service

3.3.8

Data

clear

period

transmitted.
character

the

BRK

bit

has
and

the

thg

will

requests

the

begun
load

bit

any

the

should

service

for

the

should

scanner

state

accomplish

line.

load

requests

transmission

the

after

program

BRK

the

transmitted.

time

program

When

transmitting

first

the

procedure

the

double

soon

returns

scanner

set

too

not

before

following

should

sending

should

data

the
character.

Control
EIA

standard

feature.

and

Indicator

the

line

period

The

program

the

this

state

that

may

When

indicating

Ring

break

DZ11

bit

character.

service

with

BRK

character,

models

the

data

all-zero character

DZ11

last

the

Set

the

requests

the

line

set

sending

scanner

has

each

not

characters.

program

must

also

the

that

interfaces

The

Data

The

program

uses

set

control

logic.

program

may

signals

from

Terminal

Ready

three
One

8-bit
bit

include

sense

each

set

the

state

data

signal

registers
each

data

set

to
to

control

and

of
may

the

Carrier

control

each

data

set.

access

the

DZ11

data

associated

with

the

data

logic.

There

are

set

control

logic

and

the

transmitter

and

receiver

program

under

done

should

coordination

required

Any

between

interlocks

hardware

lines.

the

each

control.

The

Data Terminal

Setting

clearing

appropriate

may

access

word
be

Ready

Data

this

instructions

signal

the

DZ11

The

Carrier

registers.

carrier

are

CAR register.
signal

program

for

line

can

examining

can

examine

can

signal

byte

off.

not

cleared

and

the

Ring

the

examining
the

is
if

(If

registers

cleared
the

(RING)

current

will
the

program

are

state

the appropriate

current

registers

program

clears

CSR.

determine

the

The

Enable

bit

turn

instructions.

DTR and Line

appropriate

these

will

DTR

determine
the

a read/write

The

but

word

the

CLR

(CAR)

program

this

with

used

the

Ready

Unibus

setting

signal

accessed.)

the

The

bit

Terminal

simultaneously

INIT

(DTR)

bit

state
the

separately

RING
by

read-only

the

bit

the

ring

using

MOVB

The
or

BITB instructions or can examine them as a single 16 bit register'
by

using

does

not

signal

not

BIT

interrupt

changes

registers
is

MOV

instructions.
the

state.

determine

necessary.

PDP-11
The
the

The

DZ11

data

processor when

program
current

should

set

control

carrier

periodically

status.

Sampling

logic

ring

sample
a

high

these
rate

3.4

The

PROGRAMMING

following

option.
DZ11

Example

The

DZ11

examples

are

sample

presented

programs

only

for

the

indicate

DZ11

how

the

used.

Initializing

initialized

instruction,

Device

five

These

can

EXAMPLES

Clearing

012737

001002

000020

001004

160100

001006

032737

001010

000020

001012

160100

001014

001374

by:

device

the

001000

the

DZ11

power-up

clear

seguence,

reset

instruction.

DZ11
START:

MOV

#20,

DZCSR

;Set

bit

;DZ11

the

control

and

;status
1$:

BIT

#20,

BNE

DZCSR

; Test

;If

bit

;set,

the

branch

;jcondition
;jand®@

the

still

true

device

;function

clear

still

i progress.

001016

000000

;The

HALT

device

;function
;and

the

scleared.
DZCSR

160100

control

and

status

address

clear

is
DZ11

complete
has

been

Example 2 - Transmit binary count pattern on one line
001000

012737

001002

000020

:
START

MOV

#20,

DZCSR

scontrol

and

DZ11

the

:Set bit

status

;reglister.

001004

160100

001006

032737

001010

000020

001012

160100

001014

001374

1$:

BIT

#20,

BNE

15§

DZCSR

:Test bit

:If

bit

;the branch

device

the

function

:clear

set,

condition

and

true

:is

still

;in progfess.
the

001070

;for

line

160102

s:character;

012737

001020

001022

MOV

#n,

DZLPR

+110

001024

parameters

:Load

001016

012737

MOV

#1,

DZTCR

bit

stop bit;

baud.

;Enable

line

stransmitter.
001026

000001

001030

160104

001032

012737

001034

000040

001036

160100

sgstatus

001040

005000

MOV

CLR

#m,

DZCSR

:Set
in

:Set

scanner
the

enable bit

control

binary

count

zero.

;pattern

and

Example

(Cont)

001042

005737

001044

160100

001046

100375

2S¢

TST

DZCSR

;Test

the

;ready
BPL

2§

transmitter

flag

110037

001052

160106

001054

105200

INCB

001056

100371

BPL

001060

MOVB

branch

condition

;is

false,

continue;

Count

DZCSR

DZ11

Control

DZLPR

DZ11

Line

DZTCR

DZ11

Transmit

Control

DZTDR

DZ11

Transmit

Data

Example

Loopback

Output
001200

received

with

data

005000

001202

012701

001204

001400

and

28§

;Increment

binary

;If

condition

branch

;false,

the

;pattern

binary

Address

count

the

receiver

console.

MOV

160100

160102

Address

"On"

CLR

Address

160104
160106

Maintenance

the

1400,

interrupt

;Set

RI1

mode.

binary

;to

zero.

;Set

jaddress

sbuffer.

count.

count

first

data

count

complete.

Pattern

Status

Parameter

Transmit

mode,

character

again.

HALT

Binary

;Load

DZTDR

test

;transmitted.

000000

RO,

15).

;If

;jotherwise
001050

(bit

Example

(Cont)
#sP,

;Initialize Stack

001206

012706

001210

001100

001212

012737

001214

001304

;jaddress

001216

000300

;recelver

MOV

;jpointer.
MOV

#INT),

RVEC

;Set

DZ11

wvector

start

interrupt

;routine.
001220

005037

001222

000302

CLR

(RVEC+2)

;Set

;status

processor

word

;receliver

001224

012737

001226

000020

MOV

#20,

DZCSR

;Set

bit

;DZ11

160100

001232

032737

001234

000020

001236

160100

001240

001374

1S:

BIT

#20

BNE

DZCSR

s Test

;if

interrupt.

the

control

and

bit

;set,

the

still

branch

;jcondition
;and

DZ11

;status
001230

for

true

device

;function

clear

still

;progress.

001242

012737

001244
001246

#PAR,

;Load

the

011070

;for

line

160102

;character;

MOV

DZLPR

parameters

bit

2 stop bits;

Example

(Cont)
;110

baud;

;parity;
001250

012737

MOV

#1,

DZTCR

;Enable

receiver
line

on.

stransmitter.
001252

000001

001254

160104

001256

012737

001260

000150

;enable

001262

160100

;jinterrupts,

MOV

#1150,

DZCSR

; Turn

scanner

;lines
001264

005737

001266

160100

001270

100375

25
:

TST

;Test

DZCSR

BPL

;If

28§

receiver

back

the

;ready

001274

160106

001276

105200

INCB

001300

001371

BNE

001302

000777

MOVB

RO,

DZTBUF

branch

; Load

loop

themselves,

transmitter

condition

continue

;jotherwise
110037

and

flag.

;false,

001272

on,

test

character

again.
to

;transmitted.

BR.

28§

;Increment

binary

;If

condition

branch

;false,

the

jpattern

;jWait

for

count

complete.

last

;transmitted
sreceived.

binary

count.

character
be

Receiver
001304

013711

001306

160102

Interrupt

Service
MOV

Routine

DZRBUF,

received

; Store

;character

memory

; table.

#100377,

001310

022721

CMP

001312

100377

+
(R1)

001314

001401

BEQ

last

for

;Check

;character.

.+2

;Branch
;true

condition

when

last

character

;transmitted
;1is
001316

000002

RTI

001320

012701

MOV

001322

001400

001324

105737

001326

177564

001330

100375

TSTB

TPS

3§

(R1),

start

memory.

;Test

see

i1f

console

ready.

;Wait,

test

and

condition

;transfer

111137

001334

177566

001336

022721

CMP

001340

100377

+
(R1)

;character.

001342

001370

BNE

;Not

; to

35S

000000

HALT

met,

console.

;Check

for

last

finished

;condition
001344

again.

character

001332

#100377,

received

buffer

;If

MOVB

pointer

;data

;1is
BPL

routine.

;Initialize

;to

3S:

received.

;Exit
#1400,

1is

:finished.

if
true.

RVEC

DZ11

Receiver

DZCSR

DZ11

Control

DZLPR

DZ11

Line

DZTCR

DZ11

Transmit

Interrupt
and

Vector

Status

Parameter

Word

Address

(Write

Control

DZTBUF

DZ11

Transmit

Buffer

Address

DZRBUF

DZ11

Receiver

Buffer

Address

TPS

Teletype

Punch

Status

TPB

Teletype

Punch

Data

and

receive
in

Example

line.

The

Transmit

Switch

pattern

(character).

001000

012737

001002

000002

Address

bits

START :

Address

(Read

Only

Address

Maintenance

SWRO00-SWRO07

MOV

Only)

#LINE,

holds

DZTCR

mode

the

desired

;Select

the

160104

001006

012737

001010

017471

data

line

;transmitting

;Choose
001004

single

;Line
MOV

#PAR,

DZLPR

one

;Select

on.

160102

eight.

selected.
desired

;parameters

line

;and

turn

; for

that

line.

level

;bits,

receiver

code,

and

:selected.

line

for

;transmitting
001012

for

stop

parity

Example

(Cont)
;19.2K

baud

;Note:

19.2K baud

;not

used

;jused

diagnostic

for

;£to

001016

000050

001020

160100

001022

005737

001024

160100

001026

100375

#N,

DZCSR

TST

Test

001030

113737

MOVB

001032

177570

DZTBUFF

001034

160106

001036

000240

SWR,

and

scanner

;Start

bit

ready).

;If

the

branch

;is

false,

the

;is

ready;

condition

transmitter
true,

;back

and

test

;Load

the

transmit

;character

;No

from

;1f

only

the

;location

again.

operation.

;to

set

bit

for

;Switch
NOP

easier

; (transmitter
BPL

scope.

;Test

DZCSR

speed

make

smaintenance

Test

can

transmit-receive

; loop

MOV

the

but

;the

012737

1is

;customer

;purposes

001014

selected

can

branch
test

This
be

changed

instruction
1

Example

(Cont)
;desired

001040

MOV

012701

#DEL,

(replace

;with

000771).

;Delay

equals

;constant

177670

;allow
;the

that

will

enough

time

receiver

done

;flag

set

000240

for

before

;recycling the tést.
;The

value

will

change

;with

baud

rate

and

;processor.

001042

105737

001044

160100

001046

100402

Test

TSTB

BMI

DZCSR

1§

The

;constant

given

1is

;good

for

19.2K

baud

;on

PDP-11/05.

;Test

bit

;done

flag.

;When

the

receiver

branch

;éondition is true,
;the

receiver

;flag
001050

005201

INC

RI1

001052

001373

BNE

TEST

set.

;Increment

;If

the

013700

1S:

MOV

DZRBUF,

delay.

branch

;condition

001054

done

;delay

not

: Read

the

DZ11

true,;

the

finished.

Example

(Cont)

001056

160102

001060

Example

000760

Transmit

and

alarm

Maintenance

001200

012706

001202

001100

001204

012737

001206

001274

001210

000304

001212

005037

001214

000306

receive

TEST

single

;jreceiver

buffer

;register

;Loop

back

;test

again.

line

using

and

silo

mode
.

MOV

#1100,

;Initialize

stack

jpointer.

MOV

#3$,

TVEC

;Initialize
;vector

CLR TVEC+2

transmitter

address.

;Initialize transmitter
;jvector

processor

status

;word.

001216

012700

001220

001304

MOV

#DBUF,

;Set

;input
;into

001222

012737

first

MOV

#1,

DZTCR

address

data

table

RO.

;Enable

line

ctransmitter.
001224

000001

001226

160104

001230

012737

MOV

001232

017470

DZLPR

001234

160102

#17470,

;jSet

line

;and

turn

parameters
the

receiver

;clock for line 0.

Example

(Cont)
012737

MOV

001240

050050

DZCSR

001242

160100

transmitter

;Enable

#50050,

001236

silo

and

;interrupt
salarm.

Turn

sscanner

and

Maintenance

smode.

001244

032737

001246

020000

001250

160100

001252

001774

1$:

BIT

#20000,

alarm.

silo

:Test

for

;Loop

until

;£lag

sets.

; Read

DZ11

DZCSR

BEQ

2S
:

MOV

DZRBUF,

alarm

silo

001254

013720

001256

160102

+
(RO)

;receiver

001260

000240

NOP

;Delay

001262

000240

NOP

;word

silo

;down

the

silo

buffer

allow

output.

filter

soutput.

001264

100773

BMI

;Data

valid

;that word
;go
001266

012700

001270

001304

MOV

#DBUF,

back

;Silo

000764

for

1§

;Do

more.

been

address
again.

says

good,

;Reinitialize

;table
001272

has

set

emptied.
data

pointer.

Transmitter Interrupt Service Routine

001274

112737

001276

000252

001300

160106

001302

000002

Data

MOVB DAT, DZTBUF ;Transmit

;character 252

RTI

Table

1304

100252

s:Word #1

1306

100252

1340

100252

:Word #16

1342

000252

:Data valid not set
is

scharacter

NOTE:

invalid

It is possible to get more than 16 words because they are

being put into the silo simultaneously with the reading of the silo.

Example 6 - Echo test on a single line.

001000

012737

(Transmit received data)

MOV #PAR, DZLPR

START:

;Load line parameters
:for

001002

011073

001004

160102

line

being

used.

;Line #3, 8 bit
scharacter,

2 stop

Example

(Cont)

ibits,
;110

001006

012737

001010

000010

001012

160104

001014

012737

001016

000040

001020

160100

001022

105737

001024

160100

001026

100375

001030

005737

001032

160160

001034

100375

001036

013700

001040

160102

001042

110037

001044

160106

MOV

#LINE,

DZTCR

parity,

baud,

and

;clock

on.

;Turn

line

s;transmitter

MOV

1S
:

#n,

TSTB

DZCSR

;turn

scanner

; (set

CSR-5)

;test

(bit

on.

for

;s RDONE
BPL

18§

TST

DZCSR

;If

bit

;go

back

;Test

not

and

test

(bit

15)

BPL

2§

MOV

RBUF,

MOVB

RO,

DZTDR

;If

bit

igo

back

again.

for

and

not
test

i Read

Received

sjword

into

s Load

character

jinto

DZ11

TBUF
for

stransmitting.

000765

set

s TRDY

; Register

001046

receiver

18§

srepeat.

set
again.

Data

dligliltall
digital equipment corporation

Printed

U.S.A.