Comtech EF Data CDM-750, Installation And Operation Manual

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CDM-750 Advanced High-Speed Trunking Modem Revision 2
Rear Panel Connections MN-CDM750
3–9
3.2.2.2 J2 | REDUNDANCY Connector, DB-9F
The 9 ‐ pin Type ‘D’ female (DB ‐ 9F) J2 | REDUNDANCY connector provides the
1:1 control interface. It provides serial communications to transfer
configuration information from the Prime to the Backup modem, and a
Fault/Clock signal to signal the switch when a fault occurs. It is intended only for connection to a
CRS ‐ 170A or CRS ‐ 180 1:1 Redundancy Switch.
The connector pinouts are as follows:
Pin # Name Signal Function Singal Type
5 MDM_COM_OUT_ENA Enable “Mdm_Comm_Out” signal LVTTL Output
9 12VOLT_OUT +12 Volts at 300 ma 12V 300 ma
4 ONLINE
Commands modem to be Online/Offline
(Use pull-up on Modem side input)
LVTTL Input
8 SER_DATA Fault Serial Data Signal from modem LVTTL Output
3 TX_IF_MUTE_B
Capability to mute modem’s Tx IF (Low=Mute)
(Use pull-up on Modem side input)
LVTTL Input
7 SER_CLK Fault Serial Clock Signal 64KHz LVTTL Output
2 MDM_COM_IN
UART comm to modem from controller
(9600 to115.2BUAD)
LVTTL Input
6 MDM_COM_OUT
UART comm. from modem to controller
(9600 to115.2BUAD)
LVTTL Output
1 GND Chassis Ground Gnd
3.2.2.3 J3 | REMOTE Connector, DB-9M
The 9 ‐ pin Type ‘D’ male (DB ‐ 9M) J3 | REMOTE connector provides the remote
control interface via an M&C computer or terminal device. It is user selectable
for either EIA ‐ 232 or EIA ‐ 485.
The connector pinouts are as follows:
Pin # Description Direction (I/O)
1 Ground –
6 EIA-485 Receive Data B * I
2 EIA-232 Transmit Data O
7 EIA-485 Receive Data A * I
3 EIA-232 Receive Data I
8 EIA-485 Transmit Data B O
4 Reserved - do not connect to this pin –
9 EIA-485 Transmit Data A O
5 Ground –
* Use for 2-wire EIA-485 operation