Ibm pc/xt, pc/at, and compatible computers – HP QMS 1660E User Manual
Page 240
Cable Pinouts
QMS 1660E Print System Reference
B-10
IBM PC/XT, PC/AT, and Compatible Computers
The following diagrams show the serial cable pinouts for IBM PC/XT,
PC/AT, and compatible computers.
»
Note:
Not all serial cables are configured as shown and may require
an additional null-modem adapter. Check with your cable vendor for
compatibility.
»
Note:
To download printer system software via the serial port, your
hardware must have RTS and CTS support. Make sure that pins 4
and 5 on the 25-pin serial cable and pins 7 and 8 on the 9-pin serial
cable are crisscrossed as shown in this diagram.
To Printer
9-Pin
To CPU XT
25-Pin
Female
To Printer
9-Pin
To CPU AT
9-Pin
Female
1
Not Used
1
Not Used
RXD
2
2
RXD
RXD
2
2
RXD
TXD
3
3
TXD
TXD
3
3
TXD
DTR
4
20
DTR
DTR
4
4
DTR
DSR
6
6
DSR
DSR
6
6
DSR
GND
5
7
GND
GND
5
5
GND
RTS
7
4
RTS
RTS
7
7
RTS
CTS
8
5
CTS
CTS
8
8
CTS
9
Not Used
9
Not Used