Installation
PSM-500/500L/500LT SCPC Satellite Modem
Page 2-6
PSM-500/500L/500L T- Rev. 0.91
2.3.1 Data Interface Pin Connections
The unit is supplied with an electronically programmable data interface assembly. Table 2-1
shows the pin assignments for the possible standard interfaces. Additional information aiding the
creation of “adaptor” cables from the unit’s 37-pin female “D” sub connector to other types of
interface connections such as V.35 “Winchester” type connector standard pin-outs or RS-232
type DB25 connector is presented in Appendix C
“Cabling Specifications”.
Table 2–1 Data Interface
Connector J3 Pin Assignment by Signal
Modem
Pin #
RS–449 Signal Name
V.35, V.36 Signal
Name
RS-232 Signal Name
*(5)
Eia-530 Signal Name
Direction
1
Shield (GND)
Shield (GND)
Shield (GND)
SHD (GND)
GND (4)
4
Transmit Data (A) –
SD A (SD-)
SD
TD A
Input
22
Transmit Data (B) +
SD B (SD+)
TD B
Input
5
Transmit Clock (A) –
SCT A (ST-)
ST
TTSETC A
Output
23
Transmit Clock (B) +
SCT B (ST+)
TSETC B
Output
6
Receive Data (A) –
RD A (RD-)
RD
RD A
Output
24
Receive Data (B) +
RD B (RD+)
RD B
Output
8
Receive Clock (A) –
SCR A (RT-)
RT
RSETC A
Output
26
Receive Clock (B) +
SCR B (RT+)
RSETC B
Output
7
RTS (A) –
RTS
RTS
RTS A
Input
25
RTS (B) +
RTS B
Input
9
CTS (A) –
CTS
CTS
CTS A
Output
27
CTS (B) +
CTS B
Output
11
Data Mode (A) –
DSR
DCR
DCR A
Output
29
Data Mode (B) +
DCR B
Output
12
TR (A) –
DTR
DTR
DTR A
Input
30
TR (B) +
DTR B
Input
13
Receive Ready (A) –
RLSD
RLSD
RLSD A
Output
31
Receive Ready (B) +
RLSD B
Output
17
Terminal Timing (A) –
SCTE A (TT-)
TSETT
TSETT A
Input
35
Terminal Timing (B) +
SCTE B (TT+)
TSETT B
Input
3
External data Clock
(transmit data clock or
receive FIFO Buffer
output Clock (A) – *(3)
Ext Data/FIFO Clock
A (-)*(3)
Ext Data/FIFO Clock
A (-)*(3)
Ext Data/FIFO Clock
A (-)*(3)
Input
21
External data Clock
(transmit data clock or
receive FIFO Buffer
output Clock (B) + *(3)
Ext Data/FIFO Clock
B (+)*(3)
Ext Data/FIFO Clock
B (+)*(3)
Ext Data/FIFO Clock
B (+)*(3)
Input
19
Signal GND
SIG GND
GND
SGND
GND
20
Common
Chassis
GND
10
Mod Fault Alarm *(2)
Mod Fault Alarm *(2)
Mod Fault Alarm *(2)
Mod Fault Alarm *(2)
OC TTL
output
