Comtech EF Data CDM-625 - Manual (Page 74)

CDM-625 Advanced Satellite Modem Revision 15
Rear Panel Connectors and Pinouts MN-CDM625
3–4
3.2.2 Terrestrial Data Connection Group
3.2.2.1 Data Interface (DB-25F)
The Data Interface connector is a 25-pin, Type ‘D’ female interface that
conducts data input and output signals to and from the modem, and
connects to customer’s terrestrial equipment, breakout panel, or
protection switch.
Table 3-2. Data Interface Connector Pinouts
Pin #
(R-L)
Generic Signal Description Direction
EIA-422
EIA 530
V.35 HSSI LVDS
Circuit
#
1 Shield – Shield FG Shield Shield 101
14 Transmit Data B DTE to Modem SD B SD B SD B SD B 103
2 Transmit Data A DTE to Modem SD A SD A SD A SD A 103
15 Internal Transmit Clock A Modem to DTE ST A SCT A ST A ST A 114
3 Receive Data A Modem to DTE RD A RD A RD A RD A 104
16 Receive Data B Modem to DTE RD B RD B RD B RD B 104
4 Request to Send A * DTE to Modem RS A RTS TA A – 105
17 Receive Clock A Modem to DTE RT A SCR A RT A RT A 115
5 Clear to Send A * Modem to DTE CS A CTS – – 106
18 (NOTE 2)
6 Data Set Ready A (NOTE 2) Modem to DTE DM A DSR – – –
19 Request to Send B * DTE to Modem RS B - TA B – 105
7 Signal Ground – SG SG SG SG 102
20 (NOTE 2)
8 Receiver Ready A Modem to DTE RR A RLSD CA A RR A 109
21 (NOTE 2)
9 Receive Clock B Modem to DTE RT B SCR B RT B RT B 115
22 Data Set Ready B (NOTE 2) Modem to DTE DM B – – – –
10 Receiver Ready B Modem to DTE RR B – CA B RR B 109
23 (NOTE 2)
11 Transmit Clock B DTE to Modem TT B SCTE B TT B TT B 113
24 Transmit Clock A DTE to Modem TT A SCTE A TT A TT A 113
12 Internal Transmit Clock B Modem to DTE ST B SCT B ST B ST B 114
25 (NOTE 2)
13 Clear to Send B * Modem to DTE CS B – – – 106
Notes:
1. When the rear-panel LED marked “1:N Active!” is OFF, all of the signals shown above are available and functional. In
addition, pins not shown are not connected, and therefore no damage will occur if other signals are connected to the
additional pins.