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Document:	-1 M7142 Serial Video Module User Guide Jun1979
Order Number:	EK-M7142-UG
Revision:	001
Pages:	50
Original Filename:	http://bitsavers.org/pdf/dec/qbus/EK-M7142-UG-001_M7142_Serial_Video_Module_User_Guide_Jun1979.pdf

OCR Text

Accessories at Supplies Group
. Merrimack, New Hampshire 03054

i·

serial video module
user guide

EK-M7142-UG-001

M7142 Serial Video Module
User Guide

digital equipment corporation • merrimack, new hampshire

1st Edition, June 1979

Copyright @ 1979 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 responsibility for any
errors which may appear in this manual.

Printed in U.S.A.

This document was set on DIGITAL's DECset-8000 computerized
typesetting system.

The following are trademarks of Digital Equipment Corporation,
Maynard, Massachusetts:
DIGITAL
DEC
PDP
DECUS
UNIBUS

DECsystem-l0
DECSYSTEM-20
DIBOL
EDUSYSTEM
VAX
VMS

MASSBUS
OMNIBUS
OS/8
RSTS
RSX
lAS

CONTENTS
Page
PREFACE
CHAPTER 1

INTRODUCTION

1.1

1.5

GENERAL DESCRIPTION .............................................................................. 1-1
MECHANICAL PACKAGING ........................................................................ 1-1
ENVIRONMENTAL SPECIFICATIONS ........................................................ 1-1
OPTIONS ........................................................................................................... 1-3
VIDEO CHARACTERISTICS .......................................................................... 1-3

CHAPTER 2

INSTALLATION

2.1
2.2
2.3
2.3.1
2.3.2
2.3.3
2.3.4
2.4
2.4.1
2.4.2
2.4.3
2.4.4
2.4.5
2.4.6
2.4.7
2.4.8
2.5

SCOPE ............................... ,............................................................................... 2-1
UNPACKING AND INSPECTION .................................................................. 2-1
INTERFACE ..................................................................................................... 2-1
Keyboard/M7142 Interface ..................................................................... 2-1
Edge Connector........ ..................................................... .......................... 2-2
Video Output Connector .... .... ..... ....... ..... .... ..... .... .......... ...... .............. ..... 2-2
Communications Port Connector... ......... ...... .... .... ................... ... ... ......... 2-3
INSTALLATION PROCEDURES .................................................................... 2-4
Jumper Configurations ............................................................................ 2-4
Data Rates Selection... ... ..... ..... ......... ....... ... ..... ........... ...... ... ............. ....... 2-4
Attributes and Attribute Control Selection .............................................. 2-6
Communications Selection ....... ....... ......... ..... .......... ... .... .... ... .... ........ ... ... 2-6
Parity Selection. ............... ......... .... ................. ................................ .......... 2-7
Voltage Selection. '" ................................................................................. 2-7
Remote Initialize Selection. .......... .... ......................... ........... .... ............... 2-8
Module Mounting...... ... ..... ......... .......... .......... .......... .............. ......... ....... 2-8
CHECKOUT PROCEDURES ........................................................................... 2-9

CHAPTER 3

PROGRAMMING

3.1
3.2

3.6
3.6.1
3.6.2
3.6.3
3.6.4

SCOPE ............................................................................................................... 3-1
CONTROL/FUNCTION CHARACTERS ....................................................... 3-1
CURSOR ADDRESSING .................... ~ ............................................................ 3-1
OPTIONAL CHARACTER SET SELECTION ................................................. 3-2
DA TA FORMATS ............................................................................................. 3-2
ATTRIBUTES........ ............................. .................. .............. ........... ................... 3-2
Reverse Video Versus Forward Video ...................................................... 3-2
Reverse Video Attribute ............................... ,.......................................... 3-2
Blink Attribute ........................................................................................ 34
Half Intensity ..................................................... , .................................... 3-4

CHAPTER 4

APPLICA TIONS

4.1

SCOPE ............................................................................................................... 4-1
FULL FEATURE TERMINAL WITH BUILT-IN MONITOR ........................ 4-1
PROCESS CONTROL MONITOR ................................................................... 4-1
SECURITY APPLICATION ............................................................................. 4-1
MULTIMONITOR APPLICATION ................................................................. 4-2

1.2

1.3
1.4

3.3
3.4

3.5

4.2
4.3
4.4
4.5

iii

CONTENTS (Cont)
Page
CHAPTER 5

DIAGNOSTICS

5.\
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9

SCOPE ................................................................................................................ 5-1
REQUIREMENTS ....................................... ~ ..................................................... 5-1
LOADING P·ROCEDURE .................................................................................. 5-2
STARTING PROCEDURE ................................................................................ 5-2
OPERATING PROCEDURE ............................................................................. 5-3
ERRORS ........................................................ ,.................................................... 5-3
RESTRICTIONS ................................................................................................ 5-3
MISCELLANEOUS ......................................................... ;...... ,.......................... 5-3
PROGRAM DESCRIPTION (SCREEN) ........................................................... 5-3

APPENDIX A

CUSTOM CHARACfER SET GENERATION

FIGURES
Figure No.
\-\

1-2
\-3
2-1
2-2
2-3
3-1
3-2
3-3
3-4
3-5
3-6
4-1
4-2
4-3
4-4
5-1
A-\
A-2
A-3

Title

Page

Port Interaction .................................... ' ................. " 1-2
Mechanical Packaging .................................................. 1-2
Video Image .......................................................... 1-3
Connector Pin Number Location Diagram ................................ 2-1
Select RS423/20 rnA Loop. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-3
Jumper and Wire Wrap Post Locations ................................... 2-5
ASCII Character Set .................. '.' ............ '................. " 3-3
Attribute Selection Flow ................................................ 3-3
Reverse Video and Blink Attribute .................... , .................. 3-4
Forward and Reverse Video Displays ..................................... 3-5
Forward Video with Blink Attribute ...................................... 3-6
HalfIntensity Wire Wrap Removal ....................................... 3-7
Full Feature Terminal .................................................. 4-1
Process Control Monitor . '.............................................. 4-2
Blink Attribute and Alarm Status ........................................ 4-2
Multilocation Tabular Data Display ..................................... 4-3
Cursor Motion Test Display ............................................ 5-4
ROM Address/ROM Content Relationship ............................... A-I
Standard Character (ASCII 0438) ........................................ A-3
New Character (ASCII 0438) ......................................... , .. A-3

TABLES
Table No.

2-1
2-2
2-3
2-4
2-5
2-6
2-7
2-8
2-9
2- IO
2-11

Title

KeyboardjM7142 Connector (J2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
M7142 Edge Connector ........................ , .......................
Video Output Connector (J I) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Comm unication Port Connector (J3). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Factory Installed Jumper Configurations .............. , .. , ...............
Data Rate Jumper Configurations .......................................
Attribute Jumper Configurations ........................................
Comm unications Jumper Configurations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Parity Jumper Configurations ..........................................
Voltage Jumper Configurations ....................... ; ...... , ..........
Remote Initialize Jumper Configurations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..

Page
2-2
2-2
2-3
2-4
2-6
2-6
2-7
2-7
2-8
2-8
2-8

PREFACE

This manual describes DIGITAL's M7142 Serial Video Module. It includes descriptions, specifications, programming, and interfacing information on the M7142. The section on applications presents
examples of how the M7142 can enhance present system operation.

vii

CHAPTER 1
INTRODUCTION

1.1 GENERAL DESCRIPTION
The M7142 module forms an integral part of a terminal. The module accepts serial ASCII encoded
data to be stored in a refresh memory to generate a display for a video monitor. The M7142 also
accepts parallel data from a keyboard terminal (on strobe demand) to generate serial ASCII output.
Interaction with the M7142 is accomplished via four ports (see Figure I-I):
•

Communication Port - Data from the communication input port is sorted to form two
internal streams of data: control characters, e.g., LF, CR, VT (see Chapter 3) are fed to the
control logic; data is fed to the data storage memory.
Data storage memory is continuously scanned and the contents are used to generate a video
output for an external monitor.

•

Keyboard Port - The keyboard port operates independent from the rest of the module. It
translates parallel ASCII data to serial data to drive the communications output port.

•

Video Port - The video port provides a data path to the external monitor for data display.

•

Power Port - Power input is dependent upon the option used (see Section 1.4).

1.2 MECHANICAL PACKAGING
The M7142 is an extended-length, double-height, single-width board. Mounting holes are provided for
stand-off mounting via handle rivets and two holes located near the module fingers (see Figure 1-2).
1.3 ENVIRONMENTAL SPECIFICATIONS
The M7142 module operates under the following conditions:
•

Environment must conform to:
Temperature SoC to 60°C
Humidity 10% to 95% (no condensation)

•

Power dissipation is based on circuit requirements of 1.8 amps maximum. If only 5 Vdc is
used, power dissipation does not exceed 9 watts. An additional 2 watts (normal) is dissipated
when the ±HV (nominal 12 volts) is enabled.

1-1

r---------~---------------------------------,

I
I CLK
I
I

CNTR'L~

BAUD RATE SEL

------,

CHARV

DATA~

SERIAL ASCII :

XMIT DATA

rt1)

r _..J

I KB PORT
I

I
L

CURSOR
&
ATTRIBUTE
LOGIC

MEMORY
VIDEO

ADIlAS

VIDEO
DATA

EXTERNAL
MONITOR

PARALLEL
ASCII

_j-_________ ,;,...,

~
. .

.!J

COMMUNI·
CATION
PORT

RCV DATA

CONTROL
LOGIC
MEM & SCROLL

. , '
.
.

DEC -15V

.. -HV

PWR
SUPPLY

LSI·11 + 12V ! ..

+HV

i~ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
L..

J
MK·0686

Figure I-I

Port Interaction

4.750±·OO2

1.219 ±.O1

()

.18Typ

HOLES ARE .125d

7.44 ±.01
M7142

8.43 ±.01

- --"

.2Typ

J;-

4.80

1~"----5.187

+.015
- .020

-I
MK·0884

Figure 1-2

Mechanical Packaging
1-2

1.4 OPTIONS
The options designated below may be either customer selected or DIGITAL selected.
•

Communication Port:
Electrical interface operates in either Electronic Industries Association (EIA) RS423 or conventional DEC 20 milliamp passive current loop.

•

Power Input:
Power input is regulated +5 Vdc at 1.2 amps typical. If the RS423 communications interface
is selected, a source of +12 volts or -15 Vdc is required at 150 milliamps typical.

•

Character Sets:
Space for two character set ROMs is available. One of two optional character sets may be
selected by the attribute.
At power up, the standard graphics are enabled. The standard character set ROM is soldered
in place. A 24-pin socket is provided for installing an optional graphics RO M. A 2716/2316
or equivalent may be used to hold two optional character sets.

•

Keyboard Power:
Keyboard power is available at the keyboard data connector (12) to allow operation with a
keyboard such as the DEC LK02. Current should not exceed 100 milliamps of + 5 volts
and/ or 10 milliamps of -12 volts.

1.5 VIDEO CHARACTERISTICS
•

The video image consists of 25 lines of 80 characters each presented in adjacent 8 X 8 dot
cells (see Figure 1-3).
Horizontal Frequency = 15.36 kHz
Vertical Frequency = 60 Hz
Horizontal scan lines per frame = 256 lines

CHARACTERS
80 TOTAL
(640 DOTS)

CHARACTER
MATRIX

8x8

-CHARACTER
LINES, 25 TOTAL
(200 DOTS)

MK·0676

Figure 1-3

Video Image

1-3

•

The standard character font is presented in a 7 x 7 dot portion of the 8 x 8 dot cells.

•

Smooth scrolling rolls a clear line into the bottom of the image display. It is used whenever
an attempt is made to move the cursor down with a line feed (LF) or a vertical tab (VT) after
the cursor has reached the bottom line.

•

Direct cursor addressing is available (VT52 compatible). See Section 3.3, CURSOR AD·
DRESSING.

•

Character attributes are available allowing selection of blink, forward and reverse video,
alternate character set, or half intensity. The selected attribute may be set/cleared with bit 8
of the received data or with ASCII characters SO/SI (Shift Out/Shift In).

•

The cursor is a flashing reversed video cell with a 500 millisecond nominal period and a
reversed duty of 60% to 80%.

1·4

CHAPTER 2
INSTALLATION

2.1 SCOPE
This chapter contains the procedures for unpacking, installing, and the initial checkout of the M7142.
More detailed checkout procedures are outlined in Chapter 5 of this manual.
2.2 UNPACKING AND INSPECTION
The M7142 is packaged in accordance with commercial packaging practices. First, remove all packing
material and check the equipment against the shipping list. Report damage or shortages to the shipper
immediately and notify the DIGITAL representative. Inspect all parts of the module for cracks, loose
components, and separations in the etched paths.
2.3 INTERFACE
This section describes the sequences of signal exchanges that occur among the M7142 and other ex ternal devices. Refer to Figure 2-1 for the pin number locations of the interfacing connectors.

J2
J3
J1

1 2 3 4 5

o0 0 0 0
o0 0 0 0

1000001

108 6 4 2

00000 000 0 0
000 0 0 Q 0 0 0 0
2018161412108 6 4 2

MK·0689

Figure 2-1

Connector Pin Number Location Diagram

2.3.1 KeyboardjM7142 Interface
The keyboard interfaces to the M7142 via a 20-pin connector (J2). Table 2-1 presents the connector pin
numbers and associated signal names.

2-1

Table 2-1 KeyboardjM7142 Connector (J2)
Pin No.

Signal Name

Pin No.

Signal Name

+5 Volts

KB4

-12 Volts

Not used

GND

KB3

KB8

BREAK (GND)

KB7

KB2

GND

KB6

KBI (LSB)

KBSTRBH

GND

KB5

Not Used

BREAK

Not Used

2.3.2 Edge Connector
M7142 edge connector pins and associated signals are presented in Table 2-2.
Table 2-2 M7142 Edge Connector
Pin No.

Signal Name

AA2,BA2

+5Vdc

AC2,A T I,BC2,BTI

GND

AB2

-15 Volts

AD2

+ 12 Volts

OTHERS

Not Connected

2.3.3 Video Output Connector
Video output is provided as RS170 compatible and as separate TTL output lines. A 5-pin MOLEX·
connector (Jl) is used with pin assignments as shown in Table 2-3. (Mating connector = DIGITAL
Part No. 12-10547; Pins = DIGITAL Part No. 12-14979.)
Composite video output provides RS 170 output generated by combining the video signal with a composite sync signal. The picture signal from the balancing level to reference white across 75 ohms is 1
volt. The synchronizing levels are imposed at 40% of the signal.
*Vendor Trademark

2-2

Table 2-3 Video Output Connector (Jl)
Pin No.

Signal Name

TimingjFreq

HORIZONTAL DRIVE H

15.36 kHzj27 f.Ls.

VERTICAL DRIVE L

60 Hzj520 f,J,s.

VIDEO HI Z

GND
RS 170VIDEO

ovolts = SYNC
0.4 volts = BLACK
1.4 volts = WHITE
For direct drive output, jumper W4 must be cut providing a high impedance source at the MOLEX*
connector, pin 3. The M7142 has been tested with the following direct drive monitors:
ITOH,
Ball Brothers,
Elston.

2.3.4 Communications Port Connector
The communciations port is a to-pin connector (J3), pinned for direct DLVII-J connection. The
electrical interface may be wired for RS423 or 20 rnA communication (see Figure 2-2). Table 2-4
presents the pin assignments and associated signal names.

WIRE·WRAP
J3

WIRE·WRAP

RCV DATA RECV DATA +

7 UA18
8

/\A19
......
UA20

UA21

UA22

20
MA

UA34

3
XMIT+

UA36

-J.)---t..-t-< XMIT RS
423

KYBD MEM
MK 0686

Figure 2-2

Select RS423j20 rnA Loop

*Vendor Trademark

2-3

Table 2-4 Communications Port Connector (J3)
PinNo.

Signal Name
CLOCK I/O

GND

XMITDATA+

XMITDATA-

GND

NOT USED/POLARIZING POINT

RCVDATA-

RCVDATA+

GND

20mA SOURCE

2.4 INSTALLATION PROCEDURES
The following sections describe the installation of the M7142 module.
2.4.1 Jumper Configurations
Figure 2-3 illustrates the locations of the various jumpers and wire wrap posts of the M7142. Verify
that the factory installed jumpers are configured per Table 2-5. Any jumper configuration changes
required for user application should be made at this time.
2.4.2 Data Rates Selection
The data rates are generated via a 13.5168 MHz crystal and selected through a dual 4-bit decade and
binary counter. The following data rates are selectable: ISO, 300, 600, 1200, 2400, 4800, 9600, 19200,
and 38400.
The UART may be configured to transmit and receive at either the same data rate or at split data rates.
Data rates are configured by connecting a jumper from the selected data rate wire-wrap pin to the
clock input pin(s) of the UART. When configuring at the same data rate, the wire-wrap pins may be
daisy-chained. Table 2-6 lists the data rates and their respective pin numbers.
The UART can be configured to operate from an external clock source via pin I of J3. Both UA26 and
UA27 must be jumpered to the external clock. Do not select a data rate pin when using an external
clock.

UUU
AAA
21 1
098
XXX

UUUUU
AAAAA
66656
o 1 293
XXXXX

UU
AA
87
XX

UUU
AAA
222
1 23
XXX

W2 X UA34
_x
UA33

_X
W1

UUU
AAA
444
123
XXX

UUU
AAA
343
809
XXX

- W7

X
X

UA24
UA25

X
X
X
X
X
X
X
X
X
X
X

UA27
UA26
UA12
UA17
UA16
UAll
UA15
UA10
UA14
UA13
UA9

X
X
X
X
X

UAl
UA6
UA5..
UA3
UA4

M7142

UA32
UA35
UA36
UA37

X
X

r--

MK-067S

Figure 2-3 Jumper and Wire Wrap Post Locations

2-5

Table 2-5 Factory Installed Jumper Configurations
Function Implemented

Jumper

+ 12 V Operation

WI (or VAl toVA5)
W2 (or VA4 to VA6)
W4

RS 170 Operation

Form Feed Receive enabled for Remote
Initialization

VA59 to VA61 to VA62

8-bit - No Parity

VAl8 to VA20
VA21 to VA23
VA34 to VA32
VA36 to VA37

EIA RS423 Operation

E52 Character Set Enabled

VA39to UA40

SI/SO (Shift In/Shift Out) Attribute
Control

Forward Video

UA41 to UA43

Blink attribute enabled

UA26 to UA27 to UA 15

9600 Data Rate selected

Table 2-6 Data Rate Jumper Configurations
FROM \

Tran smitclock
pin UA27
and/or
Receiver clock
pin UA26

TO
Pin

Data Rate

VA9
VAlO
VAll
VAl2
VAl3
VAI4
UAl5
VAl6
VA17

150
300
600
1200
2400
4800

9600
19200
38400

2.4.3 Attributes and Attribute Control Selection
Several jumpers are used for attribute and attribute control selection. Table 2-7 lists the various attribute and attribute control configurations.
2.4.4 Communications Selection
Four jumpers are used for communications selection. Table 2-8 lists the jumper configurations required for either EIA RS423 or 20 rnA current loop communications.

2-6

Table 2-7 Attribute Jumper Configurations
Jumper

Characteristic

Install to enable character set E52
Remove to enable character set XE53

Install for forward video
Remove for reverse video

UA7to UA8

Install to disable half intensity

UA41 to UA42

Install to select reverse attribute

UA41 to VA43

Install to select blink attribute

VA40* to VA38

Install to select character bit 8 for
attribute control

UA40* to VA39

Install to select SI/SO for
attribute control

*UA40 can eitber be jumpered to UA38 or UA39, but not both at the same time.

Table 2-8 Communications Jumper Configurations

FROM
VAI8
UA21
VA34
VA36

RS423

20 rnA

UA20
VA23
UA32
UA37

UA19
VA22
UA33
UA35

2.4.5 Parity Selection
As many as three jumpers can be used to select ASCII serial data format. Table 2-9 lists the jumper
configurations required to select either odd, even, or no parity.
2.4.6 Voltage Selection
As many as six jumpers (two are optional) can be used for voltage selection. Table 2-10 lists the jumper
configurations required for either + 12 volt or -15 volt operation.

2-7

Table 2-9 Parity' Jumper Configurations
Characteristic

Jumper

No Parity

UA59 to UA61 to UA62

Odd Parity

UA60 to UA61 to UA62 to UA63

Even Parity

UA60 to UA61 to UA62
and U A59 to UA60

Table 2-10 Voltage Jumper Configurations
Jumper

+12V

-15 V

W I (or UAI to UA5)
W2 (or UA4 to UA6)
VA3 to UA5
UAI to UA6

In
In
Out
Out

Out
Out
In
In

2.4.7 Remote Initialize Selection
As many as three jumpers are used for remote initialize selection. Table 2-11 lists the jumper configuration required for remote initialization.
Table 2-11 Remote Initialize Jumper Configurations
Characteristic

Form Feed Receive
Break
None
Form Feed or Break

Out
In
Out
In

In
Out
Out
In

Out
In
In
Out

2.4.8 Module Mounting
The M7142 module is mounted by one of two methods.
1.

The module can be mounted in a Digital Equipment Corporatiollcomputer backplane,
taking care that all signals (e.g., grant lines) are jumpered on the backplane as required.

The module can be mounted on a panel or chassis using nylon hardware (i.e., spacers and
#2-56 screws and nuts as required), utilizing the mounting holes in the module.
Digital Equipment Corporation has available the H807 edge connector for providing power
connection to the M7142 when used in this mounting configuration.

---------_._--

2.5 CHECKOUT PROCEDURES
Two checkout methods are available to the user:
1.

When the M7142 is used on a PDP-II system, run the diagnostic CZVTO in accordance
with the instructions distributed with the diagnostic.

To check out the M7142 without a processor, local testing can be done over the RS423 or
20 rnA communication lines.
If the M7142 is configured for RS423 operation, jumper 13-3 (XMIT DATA +) to 13-8
(RCV DATA +) to provide local testing with a user-supplied display monitor and keyboard.

If the M7142 is configured for 20 rnA current loop (passive), local testing is provided by the
following three jumpers:
13-10 (+ Voltage) to 13-3 (XMIT DATA +)
13-4 (XMIT DATA -) to 13-7 (RCV DATA +)
13-8 (RCV DATA -) to J3-9 (GND)
Once these three jumpers are installed, a user-supplied keyboard and display monitor can be
used to check the operation of the module.

2-9

CHAPTER 3
PROGRAMMING

3.1 SCOPE
This chapter contains a description of the control/function characters, direct cursor addressing, and
data formats.
3.2 CONTROL/FUNCTION CHARACTERS
The control/function characters are interpreted as non-graphic data. The following actions occur at
the terminal upon receipt of these characters from the communication port:
•

BS (backspace) - The cursor moves one position to the left, if it is not currently in its
leftmost position (left margin).

•

HT (horizontal tab) - The cursor moves one position to the right, if it is not currently in its
rightmost position (right margin).

•

FF (form feed) - The module is reinitialized, if remote initialize Form-Feed jumper is installed (34 ms of fill required).

•

CR (carriage return) ..:. The cursor moves to the left margin.

•

LF (line feed) - The cursor moves down one line. If required, a smooth scroll occurs and a
clear line is provided. If a scroll operation occurs at data rates above 19200, 512 microseconds are required before another scroll can be requested.

•

VT (vertical tab) - The cursor moves down one line as in a line feed, except the next line is
not cleared. If a scroll operation occurs at data rates above 19200, 512 microseconds are
required before another scroll can be requested.

•

BREAK (spacing condition) - An initialize sequence similar to power up initialization is
generated if remote initialize BREAK jumpers are installed.

3.3 CURSOR ADDRESSING
Direct cursor addressing allows cursor movement to any position on the screen by transmitting an
escape sequence to the module.
The ESC character followed by the Y character sets up the logic for a new cursor location; e.g.,
<ESC> <V> <Line number> <Column number>
•

<ESC> <V> = Defines cursor addressing function

3-1

•

<Line number> = one character
040 = top line (ASCII space)
041 = second line (ASCII !)

070 = bottom line (ASCII 8)

•

<Column number> = one character
040 = leftmost column (ASCII space)

157 = rightmost column (ASCII 0)
The cursor is moved to the specified column of the specified line. For example, the sequence
<ESC> <V> <» <A> places the cursor on the tenth line (because ASCII <» is 518) and in the
thirty-fourth column (because ASCII<A> is 1018; and -408 for the offset results in octal column 41).
The initial sequence should be preceded by a form feed (FF) to initialize the screen registers, if a scroll
has been performed.

3.4 OPTIONAL CHARACTER SET SELECTION
Selection of the optional character set is accomplished via the attribute select bit and the removal of
jumper W3. An optional character-generator socket is provided on the M7142. For information on
creating customer character sets, refer to Appendix A.
3.5 DAT A FORMATS
The data mode for ASCII serial input is eight-level without parity. In this case, the lower order bits
represent the appropriate character with bit 8 as the attribute select bit. If bit 8 is set, the selected
attribute is enabled for the character received.
For the 7 bits with odd or even parity mode, SI/SO can be used to select the attribute bits. When
enabled, all characters received after SO have the attribute selected. All characters received after SI
have the attribute deselected. The implemented ASCII 7-bit character set is shown in Figure 3-1.

3.6 ATTRIBUTES
Selection of the various attributes is controlled by setting ASCII bit 8 to a logical one (1) or manipulation of SI/SO and adding/deleting wire-wrap jumpers on the M7142 module (see Figure 3-2).
This section contains a description of each attribute, instructions for implementation, and illustrations
of each attribute as it appears on the screen.

3.6.1 Reverse Video Versus Forward Video
The forward video display on the CRT consists of white characters on a black background. To change
the entire display to reverse video, (black characters on a white background), jumper W5 must be
removed as shown in Figure 3-3. Figure 3-4 shows sample displays of forward and reverse video
output.
3.6.2 Reverse Video Attribute
The reverse video attribute reverses the video on a character-by-character basis. Wire-wrap UA41 to
UA42 must be installed for the reverse video function. (Refer to Figure 3-3.)

3-2

0
0
0

BIT

~ b

....
. ~

b3 b2 b,
..
ROW,

0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1

0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1

0 0
0 1
1 0
1 1
0 0
0 1
1 0
1 1
0 0
0 1
1 0
1 1
0 0
0 1
1 0
1 1

0
1
2
3
4

16
17

1
1

1
0
0

1
0
1

1
1
0

1
1
1

SP
!
*

0
1
2
3

P
Q
R
S
T
U

#
$
%

5
6
7
10
11
12
13
14
15

1
0

0
0

&,
(

BS
HT

)

LF
VT

ESC

CR
SO
SI

A
B
C
D
E

5
6
7
8
9

h
i

-Y

+
,
I

G
H
I
K

u
v

L
M
N

X
Y
Z
l

1
~

:
}-

,..,

0
MK-0688

Figure 3-1

ASCII Character Set

+5V
RBR8 H---,

+5V

UA38

cl., UA40

'O-----4I~-RATRIB

SO STRB L - - - .

RRD H

INIT L
STRB L---....J

MK-0737

Figure 3-2

Attribute Selection Flow

3-3

SHIFT LOAD}
VIDEO HOLD FLlP·FLOP

+5V

ATTRIB L

ww . . - . .

"EI

ww . "'\ WIRE.WRAP MUST BE INSTALLED
\

JUMPER MUST BE REMOVED
FOR FULL SCREEN REVERSE
VIDEO FUNCTION

FOR REVERSE VIDEO ATTRIBUTE
FUNCTION
WIRE·WRAP MUST BE INSTALLED
FOR BLINK FUNCflON

WW =PINS UA41 TO UA42 (FOR REVERSE VIDEO)
WW = PINS UA41 TO UA43 (FOR BLINK)
MK·0694

Figure 3-3

Reverse Video and Blink Attributes

3.6.3 Blink Attribute
A wire-wrap must be installed as shown in Figure 3-3 to implement the blink attribute. A series of
terminal displays is provided in Figure 3-5 to illustrate the effects of the blink attribute on the screen.
Samples are shown for both forward and reverse video. Blink duty is approximately 60 to 80070 with a
2 Hz cycle rate.

3.6.4 Half Intensity
The wire-wrap shown in Figure 3-6 must be removed to enable the half intensity attribute;

3-4

MK-0682

Figure 3-4

Forward and Reverse Video Displays

3-5

MK-0681

Figure 3-5

Forward Video with Blink Attribute

3-6

47K.n.
....--'vvv---+ 5V

VIDEO DATA L

ww
UA8

1
74LS
08
AnRIB H '--_ _

REMOVE FOR HALF
INTENSITY Fl1NCTION
MK-0677

Figure 3-6

Half Intensity Wire-Wrap Removal

3-7

CHAPTER 4
APPLICATIONS

4.1 SCOPE
This chapter contains four user applications, each intended to satisfy specific user needs.
4.2 FULL FEATURE TERMINAL WITH BUILT-IN MONITOR
Blink, half-intensity, reverse video, and alternate character set attributes are selectable by interconnecting wire-wrap posts (see Chapter 3). Figure 4-1 illustrates one of the possible applications for
the M7142. This configuration provides all the normal terminal features from a user-provided keyboard on a user-provided monitor.

M7142 r--

COMPUTER

MONITOR

I '--,
KEYBOARD
MK-0693

Figure 4-1

Full Feature Terminal

4.3 PROCESS CONTROL MONITOR
Figure 4-2 illustrates an applicable configuration, utilizing a custom character set of industry symbols
installed in the alternate character set socket on the M7142. The attribute selected is that required to
display the desired information for the process being monitored.
4.4 SECURITY APPLICATION
This application is ideal for implementation of the blink attribute. Alarm status may be represented via
the blinking characteristic with the entire or partial screen displayed in reverse video (see Chapter 3
and Figure 4-3). The optional keyboard may be used for operator inputs.
4-1

PROCESS .,5
CONTROL
DISPLAY

f--

M7142

COMPUTER

MONITOR
MK-0692

Figure 4-2

Process Control Monitor

KEYBOARD

Y
COMPUTER

FULL OR PARTIAL
REVERSE VIDEO

M7142

MONITOR

MK-0683

Figure 4-3

Blink Attribute/Alarm Status

4.5 MUL TIMONITOR APPLICATION
This application features the use of several sequential monitors (see Figure 4-4) daisy-chained to provide simultaneous display of the same data.

COMPUTER

M7142

r--

0 0

MONITOR

r---

MONITOR

MONITOR
WITH 75 OHM
TERMINATOR

MK·0691

Figure 4-4

Multilocation Tabular Data Display

4-3

CHAPTER 5
DIAGNOSTICS

5.1 SCOPE
The program described in this chapter is an acceptance test of the M7142 Serial Video Board. The
program consists of five parts, all of which require operator inspection or interaction. The program is
capable of handling multiple units in a sequential DLV II (Serial Line Unit) fashion (see Section 5.8).
NOTE
Only one M7142 is tested at anyone time.
The program defaults to the console device (see Sections 5.5 and 5.8). All characters and commands
are tested. In the keyboard character test, the BREAK and REPEAT function keys are not tested.
Part I consists of a series of test patterns displayed on the screen (see Section 5.9). The operator must
visually inspect each test pattern for error detection.
Part 2 is a keyboard character test. This test verifies that the terminal configuration is generating the
expected ASCII codes. An operator is required to follow the instructions displayed on the screen and
execute them. Because of the flexibility of different processors or options, parity bit testing must be
selected by the operator via switch 00-0 I.
Part 3 is a keyboard octal value loop. When a key is pressed, the octal value is displayed on the screen.
If the key pressed is printable, it is displayed on the screen. Some non-printable characters (such as
CTRL-C, CTRL-D .... or CR, LF.... ) have been defined in the program such that, if any of these keys
are pressed, their two-letter equivalents are displayed.
Part 4 is a keyboard echo loop. When a key is pressed, the character is echoed to the screen. No testing
of the character is performed. This characteristic provides the operator with a local mode of operation
between the M7142 and the host computer.
Part 5 is a character attribute test (most significant bit [MSB] selected). A full screen offive blocks (five
lines each) is printed. Alternate blocks have any enabled character attribute selected by setting the
MSB in each of the character codes as they are printed.

5.2 REQUIREMENTS
Equipment:
l.

A PDP-II family computer with at least 8K words of read/write memory.

5-1

An M7142 serial video board with screen and keyboard connected via a DLV 11 type interface.
•

FORM-FEED INIT must be jumper enabled.

•

SI/SO CHARACTER ATTRIBUTE SELECTION must be enabled for the default
attribute test to run correctly (Test F).

•

MSB SET IN CHARACTER CODE TO SELECT CHARACTER ATTRIBUTE
must be enabled for test M to run correctly.

•

At least one character attribute must be selected for tests F and M to run correctly.

5.3 . LOADING PROCEDURE
The normal procedure for loading binary tapes should be followed.
5.4 STARTING PROCEDURE
Control Switch Settings:
Standard PDP-ll Format
SW 15 = 1
SW 14 = 1
SW 13 = 1
SW 12 = 1
SW 10 = 1
SW09 == 1

(100000)
(040000)
(020000)
(010000)
(002000)
(00 1(00)

SW08 = 1

(000400)

Halt on error
Loop on present test
Inhibit error typeouts
Inhibit program sub-test delay
Skip keyboard character test (I)
Select non-default (non-console)
addresses for M7142s being tested
Loop on test in SWR <7:0>

Keyboard Character Test Only
SW02
=1
SWOO-Ol = 00
SWOO-Ol = 01
SWOO-Ol =10
SWOO-Ol = 11

Enable parity bit test
Even parity check
Odd parity check
Always 0
Always I
NOTE
If the computer used is an LSI·ll or one without a

switch register, the program uses locations 174 and
176 as a display register and a switch register
respectively. The operator is responsible for
loading the switch register location prior to starting
or restarting the program.
Starting Address or Addresses
200
204
210
214
220
224

Starting address of the acceptance test
Restart address of the acceptance test
Starting address of the full keyboard character test
Starting address of the keyboard octal value loop
Starting address of the keyboard echo loop
Starting address of the character attribute test (MSB selected)

5-2

5.5 OPERATING PROCEDURE
The operator must insert the correct information in the switch register when requested by the program,
or an error occurs. Once started, the test runs in its normal manner, including the execution of a
"Quick" keyboard ,test that requires operator intervention, unless SW lOis set in the switch register. If
SW 10 is not set, the program does "TIMEOUT" and continues if a key is not pressed in a reasonable
period of time.
If the M7142 is not the console terminal with its first device address at 177560, then SW07 must be set
to tell the program where it is. SW 07 must also be set if more than one M7142 is to be tested.

5.6 ERRORS
Most errors must be detected by visual inspection of patterns printed on the screen. Only the keyboard
tests result in any error reporting and typeout. Refer to the "Error Pointer Table" contained in the
diagnostic listing for type and description of errors.
The error information consists of the following:
ERRPC
VTNOW
TSTNUM
EXPT
RCVD

Location where the error was detected
Current DLVII bus address of M7142 under test
Test number of failing test
Expected input character
Received input character

5.7 RESTRICfIONS
The operator should set SW 07 if the M7142 under test is not the console terminal, or not at address
177560 (see Section 5.5).
5.8 MISCELLANEOUS
Execution Time:
Execution time varies with the data rate. The program types 'END PASS' on the console when a pass
has been completed. The keyboard loop and character test does not exit until the program is restarted.
Device Address Program Locations (at approximately 1222):
Location "FIRST" contains the first DLV11 address if several M7142s are being tested. The default is
console address 177560. Location "LAST" contains the last DLVII address if several M7142s are
being tested. Location "VTNOW" contains the current DLV II base address. If several M7142s are
being tested, their addresses are assumed to be 10 octal bytes apart.
NOTE
If locations "FIRST" or "LAST" are changed,

the operator must start the test again at location
200. The program uses the base address to update
the actual program values.
5.9

PROGRAM DESCRIPTION (SCREEN)

A - Full Screen of the Letter E
This test fills the screen with the letter E and loads the screen RAM with a single character in all
locations. This test is used to visually check the linearity and centering of the M7142jCRT system.

5-3

B - Simple Character Set
This test prints one full line of each character (codes 40 through 176) of the character set. It also
verifies that all words in the screen RAM can be loaded and the scrolling function is operational.
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
DDDDDDDDDDDDDDDDDDDDDDDDDDDDDDDD
C - Incrementing and Sliding Character Set
This test prints one full line of an incrementing character set across the full screen, starting with,the
code 40 (space). The next line hegins with the "!" character (code 41), etc. The pattern continues by
incrementing the first column character until the full character set has been exhausted.
This pattern verifies that the full character set can be displayed in each screen word.
D - Cursor Motion Test (CR, TAB, LF, BKSP, VT used) - Form-Feed initialized
This test is the basic cursor motion test using the carriage return, tab, line-feed, backspace, and vertical
tab characters.
The first part of the test prints a line of text, "carriage returns" to the left margin and then "tabs" over
the text to be sure a "tab" doesn't erase characters.
The second part of the test moves the cursor down by printing some line-feeds, prints a message, and
then backspaces over that message to be sure a backspace does not erase characters.
The third part of the test executes a series of vertical tabs to be sure a vertical tab advances the cursor
down the screen one line.
Figure 5-1 shows how the screen should look when the t~st is complete:
NOTE
The Form-Feed initialized function must be
enabled.

TAB OVER·NO CHARACTER ERASE <CR) (CR)

<LF)

<LF>

(CR)
<CR) (LF> BACKSPACE OVER·NO CHAR, ERASE
<VT>
<VT)
<VT)
<VT>
<VT>(CR)

MK·0690

Figure 5-1

Cursor Motion Test Display
5-4

E - Direct Cursor Addressing (D. CA.) - Form-Feed initialized
This test is run using the "ESC-Y" sequence and randomly fills the screen. The end result is a full
screen of 25 statements. Each statement is rotated right one character with respect to the line above it.
NOTE

The Form-Feed initialized function must be
enabled.
F - Character Attribute Test (SO/SI Selected)
This test prints a full screen of five blocks (five lines each). Alternate character blocks have any enabled
character attributes selected by CNTRL-N (SO). A CNTRL-O (SI) deselects character attributes.
NOTE

The ability to select character attributes using
SO/SI and at least one character attribute must be
enabled.
G - Scroll Speed Jump Test
This test uses sets of vertical tabs to test the scrolling abilities of the M7l42. The screen is first filled
with 25 lines of single characters across all columns. The top line contains all A characters and the
bottom line contains all Y characters. Then 3 sets of 25 vertical tabs are sent (wi.th a delay between sets)
to see ifthe screen scrolls correctly. After each set of vertical tabs, the top line should still be all As and
the bottom line should still be all Y s. This test ensures that smooth scroll and high speed jump scroll
interact properly.
H - Column Address Test
This test prints 25 lines of a full line of an incrementing character set. Each line starts with 0, followed
by 123456789:;<, and so on. Each column on the screen is filled with a single character.
This pattern verifies that each column is uniquely addressable.
I - "QUICK" Keyboard Character Test

If SW 10 is set (= 1), this test is not executed. If the keyboard is included in every pass ofthis acceptance procedure, this partial test provides a quick check of the keyboard interface (switch 10 not set).
SW 0 and SW 1 have the same use as in the full-blown keyboard character test. The full-blown test
should be run to adequately check the keyboard (see J - Full Keyboard Character Test).
Only printing characters are echoed as the keys are pressed.
J - Full Keyboard Character Test
This test is designed to verify that correct character codes and parity bit are generated when a key is
pressed. This test requires the operator to execute the instructions displayed on the screen. The operator should only press one key at a time, with some exceptions. The program informs the operator
which row to test. Only printing characters are echoed as the keys are pressed.
In testing the parity bit, SW 0 and SW 1 are used to inform the program of the expected parity. An
incorrect switch setting results in an error.
/

5-5

K - Keyboard Octal Value Loop
This loop is provided to enable the operator to examine the octal value of a character. When a key is
pressed, the octal value is displayed. If the character is a printable character, it is displayed. Codes
defined as CONTROL are displayed as two-letter mnemonics (i.e., DE = delete, BL = bell,
CL =cursor left, etc.).
L - Keyboard Echo Loop
When a key is pressed, the character is displayed. No modification or data test is performed. This test
can be used to determine if there is a UART or serial line problem.
M - Character Attribute Test (MSB o(Character Code Selected)
This test is started by using a separate starting address. It is designed to ensure that setting the MSB of
the character codes sent to the M7142 causes enabled character attributes to be displayed.
A full screen of five blocks (five lines each) is printed. Alternate blocks have any enabled character
attributes selected, using the MSB on each of the characters as they are printed.
NOTE
The ability to select character attributes using the
MSB and at least one character attribute must be
enabled.

5-6

APPENDIX A
CUSTOM CHARACTER SET GENERATION

The M7142s optional character generator socket provides two alternate custom character sets for use
in place of the standard character set. An 8716 Erasable PROM or its masked equivalent (2316) can be
used for the alternate character generator ROM.
The user defines the alternate character set and then programs it into a suitable PROM or ROM. Once
the programmed device is installed in the optional character generator socket and jumper W3 is removed, the user has access to the custom character set either by MSB selection or sending SI/SO.
(See Section 3.6 for more information.)
Figure A-I shows the relationship between the ROM add'resses and the character presented on the
video display. Note, the followi-ng features:
•

In the standard character font, the left column and the bottom row are set to zero to provide
a space between characters.

•

The right octal digit of the ROM address identifies the display scan line (row 1-8, address
0-7).

•

The three remaining octal digits of the ROM address identify the character to be displayed.

ROM
CONTENT
DISPLAY
ROM
ADDRESS POSITION
(ROW)
(OCTAL)
1 (TOP)
0440
2
0441
0442
3
4
0443
0444
5
0445
6
0446
7
8 (BOT)
0447

VIDEO
DOT
MATRIX

010
076
110
076
011
076
010
000

0000.000
00.....0

0.001000
00....10

0000.00.
00.....0

0000.000
00000000
MSB

LEFT

Figure A-I

OCTAL

LSB

..
RIGHT

MK-0680

ROM Address/ROM Content Relationship
A-I

The information below is useful in planning the characters to be presented.
•

By defining adjacent video dots to be on, abutting 8 x 8 character matrices can form continuous lines.

•

The first 408 character locations (4008 ROM addresses) are not used for displayable characters. These locations are addressed by codes reserved for control characters.

The following example illustrates the steps required to generate a custom character. Assume the standard character # (ASCII 0438) is to be replaced with a £.. The £. is then displayed whenever the
M7142 receives the code 043g.
•

First, identify the video dot matrix for the desired character (see Figure A-2).

•

Next, program the ROM. Blast location 0430g with 0348, 0431g with 042g, 04328 with 040g
0433gwith 0408, 04348with 170g, 0435gwith 0418,0436 8with 1768and 0437gwith OOOg.

•

Finally, install the newly programmed ROM. Now, whenever a # is received by the M7142,
a £. is displayed at that location of the screen (see Figure A-3).

For a completely customized character set, the procedure outlined in the example must be repeated for
each character in the set.

A-2

ROM
CONTENT
VIDEO
DOT
MATRIX

DISPLAY
ROM
POSITION
ADDRESS
(OCTAL)
(ROW)

0430
0431
0432
0433
0434
0435
0436
0437

000.0100
000.0.00

1 (TOP)

2
3

0.......

000.0.00

0.......

6
7

000.0.00
000.0.00
00000000

8 (BOT)

MSB

024
024
177
024
177
024
024
000

LSB

..RIGHT

LEFT

Figure A-2

OCTAL

MK·0678

Standard Character (ASCII 0438)

ROM
CONTENT
ROM
DISPLAY
ADDRESS POSITION
(OCTAL)
(ROW)
1 (TOP)
0430

0431
0432
0433
0434
0435

VIDEO
DOT
MATRIX

000...00
00.000.0
00.00000
00.00000
0....000
00.0000.

2
3
4
5

04~6

6
7

0437

8 (BOT)

0......0

034
042
040
040
170
041
176

00000000

000

MSB

LEFT

Figure A-3

OCTAL

LSB

.RIGHT

New Character (ASCII 0438)

A-3

MK·0679

INDEX
A
Applications
Full feature, 4-1
Process control, 4-1
Security, 4-1
Multimonitor, 4-2
Attribute
Selection, 3-2
Reverse/forward video, 3-2
Blink, 3-4
Half intensity, 3-4
Jumper, 2-4
Reverse, 3-2
Attribute Control
Character bit 8, 1-4,2-6
Shift out/shift in, 1-4, 2-6

Hardware requirements, 5-1
Startup, 5-2
Operation, 5-3
Errors, 5-3
Restrictions, 5-3

F
Form feed, 3-1

H
Horizontal tab, 3-1
I
Installation
Module mounting, 2-8
Unpacking, 2-1
Inspection, 2-1
Interfacing ports
Communication, 1-1, 1-3, 2-3
Keyboard, 1-1, 2-1, 1-3
Power, 1-1, 1-3, 2-2
Video, 1-1,2-2

B
Backspace, 3-1
Break, 3-1

C
Carriage Return, 3-1
Character font, 1-4
Character sets
Space for, 1-3
Selection, 3-2
Customization, A-I
Checkout procedures, 2-9
Communications
RS423, 2-6
20 rnA, 2-6
Connectors, 2-3
Cursor addressing, 3-1

J
Jumpers
Factory installed. 2-4
Data rate, 2-4
Attribute, 2-6
RS423/20 rnA, 2-6
Parity, 2-7
Voltage, 2-7
Remote initialize, 2-8

Data formats, 3-2
Data rates, 2-4
Diagnostics
Keyboard character test, 5-1, 5-5
Keyboard octal value, 5-1, 5-6
Keyboard echo loop, 5-1, 5-6
Character attribute, 5-1, 5-6
Test patterns, 5-1

Line feed, 3-1

o
Operating Environment
Temperature, 1-1
Humidity, 1-1
Power dissipation, 1-1

INDEX-l

INDEX (Cont)

Options
Communication port, 1-3
Power input, 1-3
Character sets, 1-3
Keyboard power, 1-3

Scroll speed jump. 5-5
Column address, 5-5
QUICK keyboard character, 5-5
Full keyboard character, 5-5
Keyboard octal value, 5-6
Keyboard echo lo()p, 5-6
Character attribute, 5-6

P
Power, 1-3,2-2
U

UART data rates, 2-4

S
Smooth scrolling, 1-4

Vertical tab, 3-1
Video
Characteristics, 1-3
Output connector, 2-2
Reverse/forward, 3-2
Image, 1-3
Frequency, 1-3
Scan lines, 1-3

Tests
Letter E, 5-3
Simple character, 5-4
Incrementing and sliding character, 5-4
Cursor motion, 5-4
Direct cursor addressing, 5-5
Character attribute, 5-5

INDEX-2

Reader's Commel

M7142 SERIAL VIDEO
MODULE USER GUIDE
EK-M7142-UG-OOI

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