2 terrestrial data connection group, 1 data interface (db-25f) – Comtech EF Data CDM-625A User Manual
Page 90
CDM-625A Advanced Satellite Modem
MN-CDM625A
Rear Panel Connectors and Pinouts
Revision 3
3–6
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 3-1. Data Interface Connector Pinouts
(R>L)
Pin #
Generic Signal Description
Direction
EIA-422
EIA 530
V.35
HSSI
LVDS
Circuit
#
13
Clear to Send B *
Modem to DTE
CS B
–
–
–
106
25
(NOTE 2)
12
Internal Transmit Clock B
Modem to DTE
ST B
SCT B
ST B
ST B
114
24
Transmit Clock A
DTE to Modem
TT A
SCTE A
TT A
TT A
113
11
Transmit Clock B
DTE to Modem
TT B
SCTE B
TT B
TT B
113
23
(NOTE 2)
10
Receiver Ready B
Modem to DTE
RR B
–
CA B
RR B
109
22
Data Set Ready B (NOTE 2)
Modem to DTE
DM B
–
–
–
–
9
Receive Clock B
Modem to DTE
RT B
SCR B
RT B
RT B
115
21
(NOTE 2)
8
Receiver Ready A
Modem to DTE
RR A
RLSD
CA A
RR A
109
20
(NOTE 2)
7
Signal Ground
–
SG
SG
SG
SG
102
19
Request to Send B *
DTE to Modem
RS B
-
TA B
–
105
6
Data Set Ready A (NOTE 2)
Modem to DTE
DM A
DSR
–
–
–
18
(NOTE 2)
5
Clear to Send A *
Modem to DTE
CS A
CTS
–
–
106
17
Receive Clock A
Modem to DTE
RT A
SCR A
RT A
RT A
115
4
Request to Send A *
DTE to Modem
RS A
RTS
TA A
–
105
16
Receive Data B
Modem to DTE
RD B
RD B
RD B
RD B
104
3
Receive Data A
Modem to DTE
RD A
RD A
RD A
RD A
104
15
Internal Transmit Clock A
Modem to DTE
ST A
SCT A
ST A
ST A
114
2
Transmit Data A
DTE to Modem
SD A
SD A
SD A
SD A
103
14
Transmit Data B
DTE to Modem
SD B
SD B
SD B
SD B
103
1
Shield
–
Shield
FG
Shield
Shield
101
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.