Comtech EF Data SDM-2020, Installation And Operation Manual

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SDM-2020 Satellite Demodulator Data Interfaces
Rev.3 A–31
0 1 0 0 1 0 1 1
8 Bits Sync 1496 Bits Payload
SYNC
DATA
DVALID
CLOCK
0 1 0 0 1 0 1 1
8 Bits Sync 128 Bits RS
Figure A-10. 204 Byte DBS Serial Format
A.5.4.2 Terrestrial Signal Definition
Refer to Table A-16 and Figure A-11 for HSSI pinout.
Table A-16. HSSI Pinout (J3)
HSSI/EIA-613 Interface Connector Pinout
Signal Function HSSI
Signal
EIA-613
Circuit
Pin # (+, -) Circuit
Direction
Comment
Signal Ground SG 102 1, 26 Mod/Demod
Receive Timing RT 115 2, 27 from DCE Demodulator
DCE Available CA 107 3, 28 from DCE Mod/Demod
Receive Data RD 104 4, 29 from DCE Demodulator
Loopback Circuit C LC undefined 5, 30 from DCE Mod/Demod
Send Timing ST 114 6, 31 from DCE Modulator
Signal Ground SG 102 7, 32 Mod/Demod
DTE Available TA 108/2 8, 33 to DCE Mod/Demod
Terminal Timing TT 113 9, 34 to DCE Modulator
Loopback Circuit A LA 143 10, 35 to DCE Mod/Demod
Send Data SD 103 11, 36 to DCE Modulator
Loopback Circuit B LB 144 12, 37 to DCE Mod/Demod
Signal Ground SG 102 13, 38 Mod/Demod
TX PSYNC
(See Note 1).
TPSYNC undefined 14, 39 to DCE Modulator
TX DVALID
(See Note 1).
TDVALID undefined 15, 40 to DCE Modulator
Reserved (to DCE) 16, 41 unused
Reserved (to DCE) 17, 42 unused
Reserved (to DCE) 18, 43 unused
Signal Ground SG 102 19, 44 Mod/Demod
Carrier Detect (lock)
( See Notes 1 and 2).
CD undefined 20 from DCE Demodulator
Demodulator Fault
(See Notes 1 and 3).
DF undefined 45 from DCE Demodulator
Modulator Fault
(See Notes 1 and 3).
MF undefined 21 from DCE Modulator
Reserved (to DTE) 46 unused
RX PSYNC
(See Note 1).
RPSYNC undefined 22, 47 from DCE Demodulator
RX DVALID
( See Note 1).
RDVALID undefined 23, 48 from DCE Demodulator
Test Mode TM 142 24, 49 from DCE Mod/Demod
Signal Ground SG 102 25, 50 Mod/Demod
Notes: