Black Box ME555A, User Manual

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44
SYNC/ASYNC FIBER OPTIC MODEM
Table A-1 (continued). Interface Signal List (Female Connectors),
Pins, and Standard Signal Names
Signal Function RS-530 DB25 Description
Pin Circuit
Local Analog Loop 18 LL A control signal, which when on,
instructs the Fiber Optic Modem to
send a Local Analog Loopback (V.54
Loop 3).
Remote Digital 21 RL A control signal which, when on,
Loop instructs the Fiber Optic Modem to
send a remote Loopback command
(V.54 Loop 2) to the remote Fiber Optic
Modem.
Test Indicator 25 TM A control signal output from the Fiber
Optic Modem; positive during any test
mode.