Microcom 326M, User Manual

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326M User’s Guide
31
Chapter 5: Communications
5.1 RS-232 Serial
The printers provide a 9 pin female D-Sub connector, on the rear panel, for RS-232 serial
communication. The printer is configured as DCE (Data Circuit-terminating Equipment) so a
NULL modem cable is not necessary. A serial data cable is required to use serial
communications, refer to the table below for correct cable configurations.
The factory settings, unless otherwise requested, are set at 9600 baud, 8 data bits, 1 stop
bit, and no parity with both hardware and software handshaking. The baud rate is user
selectable from 1200 to 115,200 and uses software XON/XOFF flow control and/or
hardware CTS handshaking.
9 to 9 Pin Cable 9 to 25 Pin Cable
State
DE-9
Pin # Signals /
Directions
PC
DE-9
Pin #
State
DE-9
Pin # Signals /
Directions
PC
DB-25
Pin #
XX 1 DCD DCD 1 HI 1 DCD DCD 8
XX 2 TXD RXD 2 XX 2 TXD RXD 3
XX 3 RXD TXD 3 XX 3 RXD TXD 2
HI 4 DTR DSR 4 HI 4 DTR DSR 20
LO 5 GND GND 5 LO 5 GND GND 7
HI 6 DSR DTR 6 HI 6 DSR DTR 6
DC 7 RTS CTS 7 DC 7 RTS CTS 4
XX 8 CTS RTS 8 XX 8 CTS RTS 5
HI 9 +5V +5V 9 HI 9 +5V -
DC = DO NOT CARE XX = INDETERMINATE
Table 8 RS-232 Cable Configurations
If XON/XOFF handshaking is used, only signals RXD, TXD, and GND are required for
proper operation. If the hardware handshaking is used the CTS and RTS signals are
required. The other signals are offered in the event that the host computer requires them.
5.1.1 RS-232 Printer Cables
The 326M and 426M printers use standard cables that may be purchased through Microcom
Corporation or a local computer supply company. A NULL-modem cable is not required
because the printer is configured as DCE.
For a 25-pin serial communication port
– Use a 25-pin female to 9-pin male cable.
For a 9-pin serial communication port
– Use a 9-pin female to 9-pin male cable.