Null Modem - Symbol VRC 6940 Product Reference Manual

VRC 6940 Product Reference Guide

Null Modem

A null modem cable is used for:
! downloading programs from a PC to a VRC 6940 terminal
unloading memory contents from a VRC 6940 terminal to a PC
!
The cable has a 16-pin male circular connector, and a 25-pin female D-Connector.
4 shows the pin-outs for both connectors.
VRC6940 16-Pin Circular Connector
Pin
1
2
3
4
5
6
7
8
D-4
Table D-4. Null Modem Pin Out Descriptions
(Male)
Name
DCD
RXD
TXD
DTR
GND
DSR
RTS
CTS
Host 25-Pin D-Connector
(Female)
Pin
20
2
3
6, 8
7
20
5
4
Table D-
Name
DTR
TXD
RXD
DSR, DCD
GND
DTR
CTS
RTS