Comtech EF Data SDM-100A User Manual
Page 131
SDM-100A Satellite Modem
Theory of Operation
Rev. 0
4–15
17
P1
35
+TT
-TT
TT
J1
5
6
37,38
31,32
SD
+5V
-5V
+S
-SD
4
22
21
34
16
DEMOD FAULT
-MC
+MC
MC
DF
15
13
16
7
14
RS
CS
MF
MOD FAULT
+R
+C
+ST
25
27
3
23
5
8
26
+RT
-RT
-ST
+12V
RT
ST
33,34
10
8
11
12
35,36
RD
RR
-12V
+RD
-RD
24
6
31
13
29
+RR
+DM
-RR
GND
DM
GND
9
1,2
39,40
4
3
INTF1
INTF0
GND
1,19,20,37
-DM
11
Figure 4-6. RS-422 Block Diagram
Table 4-1. M&C Jumper Settings (AS/4973)
Jumper
Position
Function
JP10
1 to 2
RS-485
3 to 4
RS-485
5 to 6
RS-232-C
7 to 8
RS-232-C
JP22
3 to 4
RS-485
(also 1 to 2 = SDM-100 operation)
5 to 6
RS-232-C
JP2
1 to 2
4-wire
2 to 3
2-wire
JP3
1 to 2
4-wire
2 to 3
2-wire
JP11
1 to 2
CTS shorted to TX FPGA
3 to 4
CTS shorted to M&C
5 to 6
CTS shorted to RTS (RTS Loopback)
JP6, JP7 1 to 2
32/64k ROM size
2 to 3
128/256/512k ROM size
Notes:
1. JP6 selects ROM size for U207, XILINX firmware.
2. JP7 selects ROM size for U208, DSP firmware.