CTC Union ETU-01A - RS-232 User Data Channel Connector

Appendix A. I/F Modules
77
May 2011
A.5 RS-232 User Data Channel Connector
When the ETU-01A is ordered with an RS-232 interface, the physical interface is a 25-pin female
D-Sub type connector wired in accordance with Table A-6.
SIGNAL
FUNCTION
PIN CIRCUIT DIRECTION DESCRIPTION
Protective
Ground
1 AA
↔
Chassis ground.
May be isolated from signal ground.
Signal
Ground
7 AB
↔
Common signal ground.
Transmitted
Data
2 BA To ETU-01A Serial digital data from DTE.
Received
Data
3 BB Fm ETU-01A
Serial digital data at the output of the ETU-
01A receiver.
Request to
Sent
4 CA To ETU-01A
A ON signal to the ETU-01A when data
transmission is desired.
Clear to
Sent
5 CB Fm ETU-01A Constantly ON.
Data Set
Ready
6 CC Fm ETU-01A
Constantly ON,
Except during test loops.
Data
Terminal
Ready
20 CD To ETU-01A
DTR not used, used for a received serial data
rate clock input from the DTE.
Data Carrier
Detect
8 CF Fm ETU-01A
Constantly ON, except when a loss of the
received carrier signal is detected.
External
Transmit
clock
24 DA To ETU-01A
A transmitted data rate clock input from the
data source.
Transmit
Clock
15 DB Fm ETU-01A
A transmitted data rate clock for use by an
external data source.
Receive
Clock
17 DD Fm ETU-01A
A received data rate clock for use by an
external data source.
Remote
Loopback
21 RL To ETU-01A
When on, commands ETU-01A into remote
loop back, can disable by DIPSW.
Local
Loopback
18 LL To ETU-01A
When on, commands ETU-01A into local
loop back, can disable by DIPSW.
Test Indicator 25 TM Fm ETU-01A ON during any test mode
Table A-6 RS-232 user data channel connector pin allocation