Centronics 702 User manual

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37400591 REV C AUGUST 1980 ,,J .
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OPERATORS MANUAL

TP 114 12-llO B
--WARNING--
This equipment generates, uses, and can radiate radio frequency
energy and if not installed and used in accordance with the operators
manual, may cause interference to radio communications. It has been
tested and found to comply with the limits for a Class A computing
device pursuant to Subpart J of Part 15 of FCC Rules, which are
designed to provide reasonable protection against such interference
when operated in a commercial environment. Operation of this equip-
ment in a residential area is likely to cause interference in which case
the user at his own expense will be required to take whatever
measures may be required to correct the interference.
JANUARY 1, 1981
APPROVED, CLASS A
Note: Must be used with shielded data cables only.

TABLE OF CONTENTS
SECTION 1-GENERAL INFORMATIOM PAGE
1.1 DESCRIPTION ............................................................. 1-1
1.2 SPECIFICATIONS .................................. · ......................... 1-2
1.3 PRINCIPLES OF OPERATION .................................................. 1-3
1.4 SELECTABLE/OPTIONAL FEATURES ........................................•... 1-5
1.5 ACCESSORIES ............................................................. 1-6
1.6 TECHNICAL DOCUMENTATION ................................................ 1·6
SECTION 2-INSTALLATION
2.1 PRINTER INSPECTION ....................................................... 2·1
2.2 SITE CONSIDERATIONS ...................................................... 2-1
2.3 SET-UP PROCEDURES ....................................................... 2·2
2.4 RIBBON CASSETTE INSTALLATION OR REPLACEMENT .....................•........ 2-3
2.5 LOADING PAPER .. . .. ... ... ... ... .... .. . .................................• 2·4
2.6 PAPER SPECIFICATIONS ..................................................... 2-6
2. 7 DIP SWITCH SETTING, AUTO LINE FEED ......................................... 2-6
2.8 SELF-TEST ............................................................... 2-6
SECTION 3-INTERFACE INFORMATION
3.1 PRINTER INTERFACE CONNECTIONS ............................................ 3-1
3.2 INTERFACE DRIVERS AND RECEIVERS .......................................... 3-1
3.3 INTERFACE INPUT/OUTPUT SIGNALS ........................................... 3-1
3.4 HOST-GENERATED CONTROL CODES ............................................ 3-2
SECTION 4-0PERATION
4.1 CONTROLS AND INDICATORS ................................................. 4-1
4.2 OPERATING NOTES ......................................................... 4-2
4.3 OPERATING GUIDE .......................................................... 4·2
4.4 VERTICAL FORMAT UNIT, OPERATION .......................................... 4·3
SECTION 5-0PERATOR MAINTENANCE
5.1 PREVENTIVE MAINTENANCE .................................................. 5· 1
5.2 TROUBLESHOOTING GUIDE ................................................... 5-2
702/703 OM 0591-C

SECTION 1
GENERAL INFORMATION
1.1 DESCRIPTION
The Models 702/703 are high-speed, bidirectional,
impact printers that use dot matrix techniques for
character generation. Each printer is completely
self-contained, composed of mechanical, electro-
mechanical components and a logic printed cir-
cuit board (PCB). The printed circuit board uses
microprocessor technology to minimize com-
ponents and increase reliability.
Maximum throughput is achieved with bidirec-
tional printing that seeks the shortest path to the
next line of characters when printing successive
lines of data. Print head and paper movement is
controlled by stepper motors.
The standard printer uses a 7x 7 dot matrix and
64 upper case ASCII characters for character
generation. Character sets of 64, 96, 128, 160 or
192 are also available. The major differences be-
tween the Model 702 and.703 are the print speed
and paper slew rate. These differencesare shown
in paragraph 1.2 Specifications.
This manual provides the necessary information
to install, operate and maintain the printer. This
information includes site considerations, set-up
procedures, operating instructions and operator-
level maintenance.
Figure 1-1 Model 702/703 Printer
7021703 OM 0591 ·C
1-1

1.2 SPECIFICATIONS
DATA INPUT
Data Format ................... 718 bit ASCII parallel, TTL levels
Input Code ..................... 64 character ASCII
Buffer ......................... One line character buffer
Input Gating ..................• Data Strobe is normally gated with acknowledge of previous
character.
PRINTING
Printing Method ................ Impact, character by character, bidirectional
Dot Matrix ..... · ................ Standard: 7x 7
Optional: 5x7, 7x9, 9x7, and 9x9
Print Format ................... Standard: 10 characters per inch
Optional: 12 or 15 characters per inch
Print Speed .................... MODEL 703-180 cps (7 x 7 dot matrix)
-165 cps (9 x 7 dot matrix)
MODEL 702-120 cps (7 x 7 dot matrix)
-11 Ocps (9 x 7 dot matrix)
CharacterSet .................. Standard: 64 character ASCII
Optional: 64, 96, 128, 160 and 192 character sets
Number of Copies ............... Prints original and up to five carbon copies
PAPER ADVANCE
Vertical Format ................. 6 lines per inch
Paper Entry .................... Rear and Bottom Feed
PaperSlew Rate ................ MODEL 703-15 inches per second (ips)
MODEL 702-8 inches per second (ips)
Auto Line Feed ................. Automatic line feed on carriage return (Disabled by option)
Paper Feed .................... Rear or Bottom tractor feed
17.3 inches (439 mm) maximum paper width
13.2 inches (335 mm) maximum print width
Paper Specifications ............. Refer to paragraph 2.6 for detailed specifications
PHYSICAL-ENVIRONMENTAL-ELECTRICAL
Height ........................ 9.0 inches (229 mm)
Depth ......................... 19.5 inches (495 mm)
Width ......................... 25.0 inches (635 mm)
Weight ........................ 75 lbs. (34 k_g)
Temperature ................... Operating: 40° to 100°F (4° to 38°C)
Storage: -35 ° to 130°F ( -37° to 54 ° C)
Humidity ...................... Operating: 20% to 90% (No condensation)
Storage: 5% to 95% (No condensation)
Input Voltage/Frequency ......... 115 VAC +10%, -15%; 60 Hz ±1 Hz
230 VAC +10%, -15%; 50 Hz ±1 Hz
Power Cord Length .............. 12 feet (3. 7 m)
702/703 OM 0591 ·C
1-2

1.3 PRINCIPLES OF OPERATION
Figure 1-2 is a pictorial block diagram of the
Model 702/703 printers, illustrating the relation·
ship of the electrical and mechanical com-
ponents to the logic board.
The printercontains a"microprocessor" that con-
trols printer operations. Under program control
the microprocessor, located on the main logic
board, controls the receiving of parallel data and
monitors the control panel. Also, the micro-
processor initiates movement of the print head,
carriage and paper, and monitors feedback from
the limit switches, video system, optional elec-
tronic vertical format unit, and paper empty
switch to effect proper execution of these com-
mands. It maintains arecord of the position of the
print head at all times, provides printer status in-
formation to the attached devices, and performs
other housekeeping functions.
Basically, all printer functions can be grouped in-
to one of three categories: (1) character printing,
(2) paper motion, and (3) auxiliary functions.
CIRCUIT BREAKER@
30016
INPUT
DEVICE
~TCABLE
ASSEMBLY (W2)
ELECTRONIC
VERTICAL FORMAT ~
UNIT (VFU) (OPTION)
rfV TRANSFORMER ' .
FILTER ~--=====--<>t
SPEAKER
AUDIO ALARM
(OPTIONAL)
~I
--~PO_w_E_R __ D-10-DE BRIDGES ~
. ~CITORS
PARALLEL DATA IN
CONTROL
RTP~
LOGIC BOARD
• MICROPROCESSOR
•PROGRAM
•MEMORY
• SUPPORT LOGIC
• POWER SUPPLIES
• POWER DRIVERS
LEFT MARGIN INDICATOR ~ !,..,
RIGHT MARGIN INDICATOR ~ EDP
(fJPAPER EMPTY
q ~WITCH
VIDEO
PAPER
STEPPER MOTOR
SOLENOIDS SIGNALS
VIDEO AMPLIFIER
HEAD MOTION
'
TIMING'-
FENCE ""'- '
Figure 1-2 Pictorial Block Diagram
PRINT HEAD &
CARRIAGE ASSEMBLY
CARRIAGE
STEPPER
MOTOR
7021703 OM 0591-C
1-3

CHARACTER PRINTING-Characters are printed by
selectively activating the print wires aligned in a
vertical column in the print head. As the head
moves across the p~per, the appropriate print
wires are momentarily activated, driving them
against the ribbon, paper and platen to form the
specified dot pattern.
The print commands to the print wires are
developed by programmable read-only memories
(PROM's). To extract print information, the
microprocessoraddresses a PROM memory loca-
tion for each column within a character.
As shown in Figure 1·3, the print head is attached
to the carriage assembly, which in turn is at·
tached to a rotating carriage drive belt. The car-
riage is driven in the forward or reverse direction
by the carriage stepper motor which rotates the
carriage drive belt clockwise (forward direction)
or counterclockwise (reverse direction).
VIDEO AMP.
ASSEMBLY
PAPER MOTION-Paper can be moved manually by
pushing in and rotating the platen knob, or
automatically by any of three paper motion com-
mands: line feed, vertical tab and form feed.
Paper is advanced one line by momentarily ac-
tivating the paper stepper motor, which applies
torque to the tractor unit drive gears. When using
the tractor unit with the electronic vertical format
option, vertical tab and form feed operations are
accomplished by activating the paper stepper
motoruntil the prescribed amount of paper move-
ment, programmed into the microprocessor, has
been accomplished.
The electronic vertical format option allows ver-
tical tab, form feed and bottom of form operations
to be controlled electronically by data memory.
The memory can be loaded either locally through
CARRIAGE DRIVE
STEPPER MOTOR
ELECTRONIC VFU
(OPTION)
20104
NOTE: DIRECTION SHOWN FOR
UPWARD PAPER MOVEMENT.
Figure 1-3 Character Printing/Paper Motion
702/703 OM 0591-C 1-4

a hand-fed paper tape reader or remotely through
the reader by the operatoreach time the printer is
powered-up or when a format change is required.
The memory holds the "tape image" which is
electronically "rotated" as paper is advanced.
If the electronic vertical format option is not used,
then a vertical tab operation moves paper 1 inch
(6 line feeds) and a form feed operation moves
paper 11 inches or 12 inches, as prescribed by the
customer. This feature is preset in the option
PROM, and also determines forms control if the
electronic vertical format option is installed but
memory is not loaded.
SPECIAL FUNCTIONS-As a standard feature, the
printer contains automatic motor control which
applies a holding current to the stepper motors
when no data is received.
Also a standard feature, the printer has a self-test
capability which is activated by pressing the
OVERRIDE switch while the printeris deselected.
The printer automatically prints out both
characters sets and the h~xadecimal equivalent
for each of the 32, 8-bit locations in the option
PROM.
An optional audio alarm is available for alerting
the operator of a special condition. An audible
tone from a speaker is sounded by software com-
mand (bell code-07 hex) or by a paper empty
condition.
In addition to printable character codes, the
printer also recognizes certain special control
codes. Refer to paragraph 3.4 for a list of these
control codes and the actions performed upon
receiving these codes.
1.4 SELECTABLE/OPTIONAL FEATURES
The standard printer may be equipped with
various selectable/optional features to provide
additional capabilities in the printer. The features
available are as follows:
SELECTABLE FEATURES
Auto Line Feed on Carriage Return Disabled-On
detection of a carriage return (CR) control code,
previously received data will be printed, but a line
feed (LF) will not be performed.
Inhibit Prime on Select- The feature prevents the
logic and buffer from being reset when the printer
is selected.
702/703 OM 0591-C
1-5
Inhibit Prime on Delete-This feature prevents a
delete code (Octal 177) from resetting the print
buffer. It allows the delete code to be used as a
pad character.
Inverted Data Strobe-This feature inverts the
negative-going data strobe to an active high for
control function definition and data loading.
Non-Gated Data Strobe-This feature allows the
printer to accept data before the previous
character is acknowledged.
Escape Control of Bit 8- This feature enables the
software sequence of ESC (Octal 033), Numeric 3
(Octal 063), and ESC (Octal 033), Numeric 4(Octal
069) to control the active state of bit 8.
Automatic Print on Paper Motion Command-This
feature generates a carriage return on receipt of a
line feed (LF), vertical tab (VT) ortop of form (TOF)
command, causing the line of data to be printed
before the paper motion command is performed.
Data Bit 8 Address-(A) Secondary character set
can be accessed by bit 8 high or low. (B) Single
elongated character can be controlled by bit 8
high or low. (Only (A) or (BJ can be selected.)
OPTIONAL FEATURES
Character Sets-Optional 64, 96, 128, 160 or 192
character sets are available in upper/lower case,
international or special symbols. Selection of an
alternate character set is done by bit 8. The
character sets are available in 5x 7, 7x 7, 7x 9,
9x 7, and 9x 9 dot matrix.
Condensed Print-Optional 12 or 15 characters per
inch condensed print is available in place of the
standard 10 character per inch density.
Electronic Vertical Format Unit-The optional 2 or 12
channel electronic vertical format unit (EVFU)
allows vertical tabs and form feed operations to
be controlled by data memory that stores "tape
image" which is electronically rotated as paper is
advanced. If the EVFU is not used in the printer,
then the printer automatically performs an 11
inch form feed and a 1 inch vertical tab at 6 lines
per inch.
Audio Alarm- This option generates an audible
alarm approximately 2 seconds in duration in
response to a BELL code (Octal 007) or a paper
empty condition.

6/8 LPI- This option allows, by operator selec-
tion, printing at 6 lines per inch or8 lines per inch.
Elapsed Time Indicator (ETl)-An optional indicator
showing up to 1000 hours of print time before it
has to be reset, is available to the user.
1.5 ACCESSORIES
The following printer accessories are available.
RIBBON CASSETTE (37740008-2001)-Throwaway
longlife ribbon cassettes containing 70 yards of
ribbon are available to the user.
UNIVERSAL PRINTER STAND (81100000-6070)-The
printer stand provides a rigid pedestal for mount-
ing the printerand allows for bottom or rear paper
loading.
FORMS RECEIVING TRAY (65008166-6002)-The
forms receiving tray collects and neatly stacks
forms exiting from the rear of the printer. NOTE:
The forms receiving tray is standard when the
printer stand option is chosen.
OUIETIZED CABINET -The quietized cabinet is
specifically designed to absorb noise from the in-
terior of the printerand along the paper path. This
accessory enables users to operate their printers
in a low noise level work environment.
FRONT FEED UNIT (63703215-6001)-The front feed
unit allows users to handle ledger cards and cut
forms in either single or multipart form.
PRINTER EXERCISER (66000100-4001)-The printer
exerciser is a self-contained unit used for the off.
line testing of the printer with parallel interface.
The unit includes 19 switch selected test controls
and a 10 ft. cable.
PRINTER MINI-EXERCISER (6600310-4001 )- The
mini-exerciser is a self-contained unit and in-
cludes an integral connectorwith two switches to
control line length and different character forma-
tions. In combination the two switches produce
four test sequences.
7021703 OM 0591-C
1-6
PRINTER MINI-II EXERCISER (66003107-5001)-A
self-contained, hand held off-line tester that tests
the parallel printer. The Mini-II is programmable
by front panel switches. A 43 inch cable is pro-
vided with the unit.
TOOL KIT (63002399-6001 )-A tool kit containing
all the necessary tools (screwdrivers, nut drivers,
pliers, etc.) to maintain the printer is available to
the user.
1.6 TECHNICAL DOCUMENTATION
The following technical documentation
documents the Models 702 and 703 printers in
detail. Contact the Customer Service Department
at Centronics for these publications.
UNPACKING/REPACKING INSTRUCTIONS
(37407827-9001)-The unpacking/repacking in-
structions are attached to the outside of the ship-
ping container and provides all the necessary in-
formation to unpack the printer.
TECHNICAL MANUALS (Model 702-37400550-9001,
Model 703-37400450-9001 )- The technical
manual is used by qualified field service person-
nel. The manual contains detailed information on
printer theory of operation, maintenance, ad-
justments and removal/replacement procedures.
A print set containing schematics, assembly and
wiring diagrams for all printed circuit boards is
also contained in the manual.
ILLUSTRATED PARTS MANUALS (Model 702-
37400552-9001, Model 703-37400452-9001)-The
illustrated parts manual contains illustrations and
lists of materials detailing all assemblies and
sub-assemblies down to a piece part level. The
manual also contains a numerical index, listing
every part contained in the printer in numerical
order and reference to a figure and index number
to show the location of the part.
TECHNICAL INTERFACE MANUALS-A technical
manual covering in detail the optional interface
boards is available to the user. The specific
manual will be shipped with the installed inter-
face board.

CDCC
PART NO.
63701381-5001
81100000-6070
65008166-6001
37740008-2003
63002399-6001
37400591-9001
37400701-9001
37400591-9001
37400453-9001
37400550-9001
37400450-9001
37400700-9001
37400453-9001
37400550-9001
37400450-9001
ACCESSORIES ORDER FORM
MODEL 702/703/704
ACCESSORY
QUANTITY
DESCRIPTION
Acoustic Cover
Print Stand (unassembled)
Forms Receiving Tray
"7-Meg" Ribbon Cassette
Tool Kit
Operators Manual (702/703)
Operators Manual (704)
Operators Manual (704-11/12)
704-11/12 Addendum
Technical Manual (702)
Technical Manual (703)
Technical Manual (704)
704-11/12 Addendum
Illustrated Parts Manual (702)
Illustrated Parts Manual (703)
UNIT
TOTAL
PRICE PER ITEM
$ 40.00
150.00
38.00
178.08/doz.
56.00
9.00
9.00
9.00
N/C
35.00
35.00
35.00
N/C
20.00
20.00
SALES TAX
ORDER TOTAL
SHIP TO:
BILL TO: (If different from "SHIP TO")
Dept. Phone Number Dept. Phone Number
Firm Name Firm Name
Address Address
City State Zip City State Zip
CustomerNumber Purchase Order Number Customer Number
Ordered by
PAYMENT METHOD:
D UPSCOD
Payment Terms:
For orders less than $100.00:
Attention of
0 CHECK ENCLOSED
ewe pay freight) D
BILLME
(Current CDCC
Customers only)
Will be shipped UPS COD; unless payment for the full amount of the order, including sales tax, is enclosed.
With prepayments we pay the shipping costs.
For orders in excess of $100.00:
Same terms as above; or, if you currently have an account with Centronics, we can bill you.
Prices subject to change without notice.

SECTION 2
INSTALLATION
2.1 PRINTER INSPECTION
Visually inspect the printer for signs of damage
received during shipment. Immediately notify the
common carrier of any damage.
NOTE ---------.
Any attempttooperate a damaged printervoids the warranty
and may cause further damage.
19.5" ---i
(495mm)l I
v-Y2tJ
2.2 SITE CONSIDERATIONS
When selecting a site to install the printer, the
following information should be taken into con-
sideration.
PRINTER DIMENSIONS-Refer to Figure 2·1.
00768
TABLE TOP OPERATION
32.0"
(812 mm)
702/703 OM 0591 ·C
36.0" max
----- (914 mm) _______ _
r-- 24.5" --1
I ~ '"' .... , ;;::ftfl--1 t
I
l:
'-
I 20.0" I
i---1so8 mm)---j
PRINTER STAND OPERATION
Figure 2-1 Printer Dimensions
2·1
.....
8.0"
(203mm)
j1
LJ

WEIGHT
Printer: 75 lbs. (34 kg.)
Stand: 22.5 lbs. (10.2 kg.)
TEMPERATURE
Operating: 40° to 100°F (4° to 38°C)
Storage: -35° to 130°F (-37° to 54°C)
HUMIDITY
Operating: 20% to 90% (No condensation)
Storage: 5% to 90% (No condensation)
ELECTRICAL
115 VAC +10%, -15%; 60 Hz ±1 Hz
230 VAC +10%, -15%; 50 Hz ±1 Hz
Power Cord Length: 12 ft. (3.67 meters)
POWER
INDICATOR
2.3 SET-UP PROCEDURES
The following procedures detail the set-up of the
printer prior to operation at the installation site.
Refer to Figure 2-2 and perform the following:
1. Note any discrepancies in general printer
appearance.
2. Remove the top cover from the printer and
while manually moving the print head from left
to right check the following:
A. Ensure the optics block under the video
amplifier does not contact the timing
fence.
00773
$
POWER CORD
NOTE: ALWAYS USE A 3·WIRE
GROUND OUTLET.
INTERFACE
CONNECTOR
I
Figure 2-2 Set-Up Procedures
7021703 OM 0591-C
2-2

B. Ensure the carriage arms do not contact
the ready to print (RTP) and end of print
(EOP) switches.
NOTE -------
If either of the above two conditions occurs, refer to the ad-
justment section in the Technical Manual.
3. Loosen penetration control knob, move knob
backwards away from platen, and insert ribbon
cassette and paper as described in paragraphs
2.4 and 2.5.
4. Check the setting of DIP switch No. 1, Auto
Line Feed Enable/Disable, per paragraph 2.7.
HEAD PENETRATION (SINGLE PART FORMS)
1. Move _penetration control knob as far forward
as possible.
2. Tighten penetration control knob.
HEAD PENETRATION (MULTI-PART FORMS)
1. While manually moving print head across the
page, increase print head penetration by mov-
ing penetration control knob forward until
smudging occurs.
2. Move penetration knob backward just to the
point of no smudging.
3. Tighten penetration control knob.
PRINTER POWER/SELECT
1. Plug printer into appropriate A.C. outlet.
Always use a 3-wire grounded outlet.
2. Ensure power switch on rear of printer is OFF
and connect printerto desired input device via
interface connector.
3. Set power switch to the ON position and
check/perform the following:
A. Ensure SELECT lamp on the operators
panel is extinguished.
B. Press TOP OF FORM switch on operatoi:s
panel and rotate platen to adjust paper to
top of form position.
C. Depress SELECT switch to enable printer
to receive data.
702/703 OM 0591-C
2-3
2.4 RIBBON CASSETTE INSTALLATION
OR REPLACEMENT
The printer uses a throw-away 70 yard cassette
(37740008-2001). To install or replace the
cassette, refer to Figure 2·3 and perform the
following:
1. Turn power off and remove top cover.
2. Move carriage to center position in printer.
Loosen and move penetration control knob
away from platen.
3. If replacing existing cassette, move cassette
latch towards front of printer and remove
cassette, taking care not to damage ribbon
shield and guide. Discard the used ribbon
cassette.
.---------------------------- NOTE --------------------------.
Insert the ribbon guide card supplied with the new cassette
between the ribbon shield and guide.
FRONT COVER
Figure 2-3 Ribbon Cassette Installation or
Replacement
00777

4. Hold new cassette above print head and lower
it, tipping the rear edge of the cassette
downward so that it clears the edge of the
front cover.
5. Lower cassette until retaining tab rests on
sloping portion of retaining latch with locator
pin aligned with slot in cassette and ribbon be-
tween rear paper guide and ribbon guide card.
6. Carefully press cassette downward until latch
snaps into position above retaining tab.
Assure the ribbon is properly positioned be-
tween rear guide card and rear ribbon guide.
7. Turn ribbon drive gear knob clockwise several
turns toassure properengagement of cassette
with cassette drive gear and to assure proper
ribbon movement between rear ribbon guide
and ribbon guide card.
8. Remove ribbon guide card, reset penetration
control knob and install top cover.
2.5 LOADING PAPER
Paper may be installed two ways in the tractor
drive assembly; rear feed or bottom feed. The
following procedures detail loading of the paper
both ways.
TRACTOR DRIVE, REAR FEED
1. Ensure power is off and remove top clear
cover. Refer to Figure 2-4.
2. Loosen and move penetration control knob
away from platen.
3. Release tractor feed locking levers, then tilt
tractor feed unit back so that tractor feed
pins face up.
4. Open paper guides and feed paper
underneath tractor assembly and up into left
pin feed tractor. Close left paper guide to
secure paper. Adjust right pin feed tractor to
accomodate paper width. Ensure paper holes
are aligned so that top sheet is parallel with
top of printer. Close right paper guide.
5. Swing tractor feed unit forward and down.
Lift column scale/tear bar. Release paper ten-
sioner by rotating knob upward.
6. Feed paper under platen and rotate platen
knob until paper is fed around platen and up
between platen and column scale/tear bar to
top of pin feed tractors.
7. Open paper guides and align paper so that
top of paper is parallel with top of printer.
Close paper guides.
8. Adjust pin feed tractors so that first character
prints in desired column on paper.
9. When properly adjusted, secure tractor lock-
ing levers, lower column scale/tear bar, ad-
just paper tension with tensioner wheel, and
readjust penetration control knob.
10. Replace top clear cover, turn power on and
depress PRINT switch to enable printer to
receive data.
Figure 2-4 Loading Paper, Rear Tractor Drive
702/703 OM 0591-C
2-4

TRACTOR DRIVE, BOTTOM FEED
1. Ensure power is off and remove top clear
cover. Refer to Figure 2-5.
2. Loosen and move penetration control knob
away from platen.
3. Release tractor feed locking levers.
4. Open paper guides and lift column scale/tear
bar.
COLUMN SCALE/
TEAR BAR
5. Place box of paper underneath printer as
shown in Figure 2-5 and feed paper up
through bottom ofprinterbetween platen and
column scale/tear bar up into tractor feed.
6. Once paper is installed, lower column
scale/tear bar, close paper guides, set tractor
feed locking levers and adjust penetration
control knob.
NOTE --------.
Forbest results, remove paper from box and ensure paper is
centered and fed straight up into printer.
00761
TRACTOR FEED
LOCKING LEVER
Figure 2-5 Loading Paper, Bottom Tractor Feed
702/703 OM 0591-C
2-5

2.6 PAPER SPECIFICATIONS
Acceptable paper is continuous fan-fold, edge
perforated paper conforming to the specifica-
tions illustrated in Figure 2-6.
DD763
Figure 2-6 Paper Specifications, Tractor Drive
@
@
AUTO LF
ENABLED
DIP NO. 1
•
AUTO LF
DISABLED
PAPER SPECIFICATIONS, TRACTOR DRIVE
A. FORM LENGTH: 3.0" to 14.0" (75 mm to 355 mm);
[11" (279 mm) is recommended]
B. PAPER WIDTH: 12 .1 " ( 307 mm) maximum
(Other Specifications not Illustrated)
FORM THICKNESS: 0.030" (0.75 mm) maximum
PAPER WEIGHT: Single-Part Form-15 to 20 lb
Multi-Part Form (5-part maximum)-Original-12
to 15 lb
Copies-9to121b (last copy 151b)
Carbon Paper- 7V2 lb with medium hardner
2-. 7 DIP SWITCH SETTING, AUTO LINE
FEED
The auto line feed is enabled or disabled by DIP
NO. 1, switch 3, on the operator's panel. Figure
2-7 details the setting of the switch.
2.8 SELF- TEST
The self-test feature is activated by depressing.
the OVERRIDE switch while the printer is
deselected. The printer automatically prints out
both character sets and the hexadecimal
equivalent for each of the 32, 8-bit locations in the
option PROM.
@
Ill DIP NO. 1
CONTROL PANEL ASS EMBLY
I Remove printer front cover
to access switches.)
DD96D
Figure 2-7 DIP Switch Setting, Auto Line Feed
2-6

SECTION 3
INTERFACE INFORMATION
3.1 PRINTER INTERFACE CONNECTIONS
A 36-pin connector (Amphenol 57 Series) located
in the rear of the printer provides the means for
connecting the printer to the input device. The
pin-outs of the printer interface connector are
shown below.
PIN
SIGNAL
1
DATA STROBE
2
DATA BIT 1
3
DATA BIT 2
4
DATA BIT 3
5
DATA BIT 4
6
DATA BIT 5
7 DATA BIT 6
8
DATA BIT 7
9
DATA BIT 8
10 ACKNOWLEDGE (ACKNLG)
11 BUSY
12
PAPER OUT (PE)
13
SELECT (SLCT)
14
GROUND
15
OSCILLATOR (OSCXT)
16 GROUND
17
CHASSIS GROUND
18
+5V
19
TWISTED PAIR GROUND
20 TWISTED PAIR GROUND
21 TWISTED PAIR GROUND
22 TWISTED PAIR GROUND
23
TWISTED PAIR GROUND
24 TWISTED PAIR GROUND
25 TWISTED PAIR GROUND
26
TWISTED PAIR GROUND
27
TWISTED PAIR GROUND
28
TWISTED PAIR GROUND
29
TWISTED PAIR GROUND
30
INPUT PRIME RETURN
31 INPUT PRIME
32 FAULT
33 GROUND
34
NOT USED
35 NOT USED
36 NOT USED
702/703 OM 0591-C
3-1
3.2 INTERFACE DRIVERS AND RECEIVERS
Figure 3-1 details the voltage range for the inter-
face drivers and receivers. The interface receivers
are terminated by 1k ohm resistors to +5V.
LO= 0.4V
@ 7 mA
lk
+SV
LO = 0.4V
@ 16 mA
RECEIVER
DRIVER
HI = 2.4V
@ 0.0 mA
00955
HI= 2.4V
@ 400 uA
All input/output signals are TTL compatible
Figure 3-1 Interface Drivers and Receivers
3.3 INTERFACE INPUT /OUTPUT SIGNALS
DATA STROBE (Host Generated)-This negative
going pulse is used to transfer the incoming data
into the printer logic. The pulse duration must be
a minimum of 1.0 microsecond.
DATA LINES (Host Generated)-The eight data lines
DATA BIT 1-DATA BIT 8 contain the ASCII
character data information. Data bit levels are
positive true logic. The high logic level of each
data line must be settled at least 1.0 microsecond
before the leading edge of the strobe pulse and
remain at high at least 1.0 microsecond after the
trailing edge of the strobe pulse.

INPUT PRIME (Host Generated)-This signal causes
the print head to return to the left margin and
resets the printer logic on the trailing edge of the
signal.
ACKNOWLEDGE (Printer Generated}-This negative
going signal is used to verify the transfer of in-
coming data or to signify the end of a functional
operation. Once a code, character or control, is
sent to the printer, an acknowledge pulse must
be received before a new code can be sent.
NOTE: If the NON-GATED DATA STROBE feature
is selected, the printer can accept new data
before the previous character is acknowledged.
BUSY (Printer Generated)-This high going signal is
used to give a positive DC level signal indication
during the time when the printer cannot receive
data. It is also positive when the paper empty or
the fault status line is high.
EXTERNAL OSCILLATOR (Printer Generated}-The ex-
ternal oscillator (OSCXT) is a 90-200 kHz oscillator
used for external interface timing.
PAPER EMPTY (Printer Generated)-A high level
signal that indicates the printer is out of paper.
SELECT (Printer Generated)-A high level signal in-
dicating the SELECT switch has been depressed
or a selectcode has been received and the printer
is ready to accept data.
3.4 HOST-GENERATED CONTROL CODES
Control codes are sent to the printer along with
character codes in the input data lines. Control
codes are interpreted as instructions by the
printer. The following table is a summary of the
control codes recognized by the printer.
MNEMONIC FUNCTION
LF
Line Feed
CR
Carriage Return
DC1 Select
DC3
Deselect
VT
Vertical Tab
FF
Form Feed
DEL
Delete
so
Elongated Characters
BEL Audio Alarm
702/703 OM 0591-C
3-2
LINE FEED (LF) CODE-If the printer is in the select
mode, receipt of the line feed code will cause im-
mediate advance of one line.
VERTICAL TAB (VT) CODE-If the vertical tab code
is received while the printer is selected, the code
is processed and then acknowledged. The ver-
tical tab code will not be processed or
acknowledged when the printer is deselected.
If VFU data is loaded in the RAM, receipt of a VT
code will cause paper to advance to the next se-
quential vertical tab location. If VFU data is not
loaded in the RAM, receipt of a VT code will
cause paper to advance to a pre-set default VT
location. Default VT locations are located at6-line
intervals.
FORM FEED (FF) CODE-If the form feed code is
received while the printer is selected, the code is
processed and acknowledged. The form feed
code will not be processed or acknowledged
when the printer is deselected.
If VFU data is loaded in the RAM, receipt of a FF
code will cause the paper to advance to the next
sequential form feed (top of form) location.
If VFU data is not loaded in the RAM, receipt of a
FF code will cause the paper to advance to a pre-
set default FF location. Default FF locations are
located at 66 or 72-line intervals.
CARRIAGE RETURN (CR) MODE-If the printer is in
the select mode and printable characters have
been received, receipt of a carriage return code
will cause immediate printing. A carriage return
code is not acknowledged when the printer is
deselected.
OCTAL DECIMAL HEXADECIMAL
012 10
QA
015 13 OD
021 17 11
023
19 13
013
11 OB
014 12 oc
177 127
7F
016
14 OE
007 05 07

ELONGATED CHARACTER (SO) CODE-If the printer
is selected and receives a "SO" code, characters
printed from the buffer will be elongated. This
mode will be cancelled on receipt of a DEL code,
an end of print command, or an input prime.
The number of elongated characters allowed per
printable line should not exceed one half the buf·
fer's character capacity.
SELECT (DC1) CODE-Receipt of this code selects
the printer, independent of the operator's panel.
7021703 OM 0591-C
3-3
DESELECT (DC3) CODE-Receipt of this code
deselects the printer, independent of the
operator's panel.
DELETE (DEL) CODE-If the DEL code is received
when the printer is in the select mode, the printer
logic will be reset.
AUDIO ALARM (BEL) CODE-Receipt of this code
with the printer in the select mode will cause the
optional speaker to generate an audible tone for
approximately two seconds.

SECTION 4
OPERATION
4.1 CONTROLS AND INDICATORS
Figures 4-1 and 4-2 illustrate all the controls and
indicators on the printer mechanism and
operator's panel.
POWER SWITCH-When set to the ON positon, ap-
plies power to printer circuits.
PAPER TENSIONER-Adjusts paper tension for pro-
per paper feeding.
PLATEN KNOB-When manually pushed in and
turned, adjusts vertical paper position in printer.
PENETRATION CONTROL KNOB-Adjusts print head
penetration for optimum print quality.
SELECT LAMP-When lit, indicates printer is
selected.
VFU LAMP (Optional)-When lit, indicates optional
electronic VFU is properly loaded.
ALERT LAMP-When lit, indicates error condition
that is operator correctable, such as paperempty
or paper handling malfunction.
POWER LAMP-When lit, indicates power is on.
LINE FEED SWITCH-When depressed, causes
paper to advance one line.
TOF SWITCH-When depressed causes paper to
advance to top of next form as governed by op-
tional Vertical Format Unit (VFU).
00769
POWER SWITCH
PAPER TENSIONER
Figure 4-1 Controls, Printer Mechanism
702/703 OM 0591 ·C
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