Data Interface Connector; Table 2. Data Interface Connector Pin Assignments - Comtech EF Data CDM-570L Installation And Operation Manual

CDM-570L Satellite Modem with IP Module

5.2 Data Interface Connector

The Data Interface connector, a 25-pin D type female, conducts data input and output
signals to and from the modem, and connects to customer's terrestrial equipment,
breakout panel, or protection switch. Refer to Table 2 for pin assignments.
THE MODEM IS ALWAYS ASSUMED TO BE DCE

Table 2. Data Interface Connector Pin Assignments

Generic Signal
Pin #
description
2 Transmit Data A
14 Transmit Data B
24 Transmit Clock A
11 Transmit Clock B
15 Internal Transmit
Clock A
12 Internal Transmit
Clock B
3 Receive Data A
16 Receive Data B
17 Receive Clock A
9 Receive Clock B
8 Receiver Ready A
10 Receiver Ready B
5 Clear to Send A *
13 Clear to Send B *
4 Request to Send A *
19 Request to Send B *
7 Signal Ground
1 Shield
Notes:
•
When the rear-panel switch marked "1:N Switch" is in the OFF position, 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.
•
When the rear-panel switch marked "1:N Switch" is in the ON position, the higlighted signals are
no longer available. Furthermore, pins 6, 18, 20, 21, 22, 23 and 25 are reserved for use by the 1:N
system. DO NOT connect signals to any of these pins in this mode. Certain pins have DC voltages
present that may damage equipment other than a Comtech EF Data redundancy switch.
•
For X.21 operation, use the EIA-422 pins, but ignore Receive Clock if the Modem is DTE, and
ignore Transmit clocks if the Modem is DCE.
Direction
DTE to Modem
DTE to Modem
DTE to Modem
DTE to Modem
Modem to DTE
Modem to DTE
Modem to DTE
Modem to DTE
Modem to DTE
Modem to DTE
Modem to DTE
Modem to DTE
Modem to DTE
Modem to DTE
DTE to Modem
DTE to Modem
-
-
20
EIA-422
V.35
EIA-530
SD A SD A
SD B SD B
TT A SCTE A
TT B SCTE B
ST A SCT A
ST B SCT B
RD A RD A
RD B RD B
RT A SCR A
RT B SCR B
RR A RLSD
RR B -
CS A CTS
CS B -
RS A RTS
RS B -
SG SG
Shield FG
Revision 1
MN/CDM570L.IOM
EIA-232 Circuit #
BA 103
- 103
DA 113
- 113
DB 114
- 114
BB 104
- 104
DD 115
- 115
CF 109
- 109
CB 106
- 106
CA 105
- 105
AB 102
AN 101