Specifications

09/01/01 4:29 PM A-1
Appendix A
Pin Assignment for
Subchannels with DB-25
Connectors
Table A-1 Pin Assignment for Subchannels with DB-25 Connectors
V.24 RS-232 Pin Signal Description
101 AA 1 Protective Ground Chassis ground. May be isolated from
signal ground (
see Section 2-4
).
102 AB 7 Signal Ground Common signal and DC power supply
ground.
103 BA 2 (14) TD - Transmit Data Serial digital data into FLM-1, end-to-end.
104 BB 3 (16) RD - Receive Data Serial digital data output from FLM-1,
end-to-end.
105 CA 4 (19) RTS - Request To Send A positive level to FLM-1 when data
transmission is desired, shorted to CTS.
106 CB 5 (13) CTS - Clear To Send A positive level from FLM-1 (if data
transmission is possible), shorted to RTS.
107 CC 6 (21) DSR - Data Set Ready A positive DC voltage (+8V) from FLM-1
indicating that the unit is powered.
109 CF 8 (12) DCD - Receive Line Signal
Detector (Carrier Detect)
A positive level from FLM-1 except when
either a sync loss occurs or remote
loopback is performed.
−−
9 This signal (+8V) is reserved for data set
testing and for powering miniature
modems
10 This signal (-8V) is reserved for data set
testing and for powering miniature
modems
Note
Pin numbers in parentheses are for the secondary channel, available when using a
channel doubler cable (working in 12-channel operation mode).