Epson SQ-1170 Service Manual page 23

Table 1-11. Connector Pin Assignments and Signal Functions (Cont.)
Pin
Signal Name
No.
14
15
16
17 Chassis GND
18
19 to 30
I NIT
31
3 2 ERROR
3 3
3 4
3 5
3 6
NOTES: 1. "Dir." indicates the direction of the signal flow as viewed from the printer.
2.
"Return Pin No." denotes a twisted-pair return line.
3. The cable used must be shielded to prevent noise.
4. All interface conditions are based on TTL levels. Both the rise and fall times of all signals
must be less than 0.2Ks.
5. The AUTOFEED-XT
6. The SELECT-IN signal can be set to LOW by jumper 1.
7. Printing tests, including those of the interface circuits, can be performed without using
external equipment by setting DATA 1 -DATA 8 pins to the STROBE signal.
Return Dir.
Pin No.
--
IN
. . --
16 IN
OUT
-- . .
O U T
--
IN
signal can be set to LOW by DIP switch 2-4.
1-15
Functional Description
If LOW
when the printer is initialized, the printer
automatically performs a
CR code (Auto LF).
Not used.
Ground for twisted-pair grounding.
Chassis ground level of printer.
Not used.
Ground for twisted-pair grounding.
Pulse (width: 50ws, min., active LOW)
initialization.
LOW
indicates an error has occurred in the printer.
Ground for twisted-pair grounding.
Not used.
Always HIGH. (Pulled up to +5V through 3.3K ohm
resistor.)
when the printer is initialized, DC l/DC3
If LOW
control is disabled.
line
feed upon input of the
input for printer