Comtech EF Data CRS-170 - Manual (Page 27)

CRS-170 1:1 Redundancy Switch Revision 1
Installation and Operations Manual MN/CRS170.IOM
29
4.1.2 M
ODEM
B C
ONTROL
C
ONNECTOR
The Modem B Control connector is a 9-pin D female interface located on the
modem side of the L-Band Switch Module. Refer to Table 3 for pin assignments.
Pins 2, 3, and 4 carry signals looped through the switch module from Modem A to
Modem B, while pins 6, 7, and 8 loop the same signals from Modem B through to
Modem A. The 12VDC input, which is diode OR’ed with the corresponding
12VDC input from modem A, powers the switch module.
Table 3. J3B - Modem B Control Connector Pin Assignments
Pin # Signal Function Signal Name Direction
1 Signal Ground Ground -
2 Modem A 232 Tx AUX_SER_TX_A Out
3 Modem A Online Indication ONLINE_OUT_A Out
4 Modem A Fault Indication /FAIL_OUT_A Out
5 Signal Ground Ground -
6 Modem B 232 Tx AUX_SER_TX_B In
7 Modem B Online Indication ONLINE_OUT_B In
8 Modem B Fault Indication /FAIL_OUT_B In
9 +12 VDC +12VDC In