Specifications

DMD20/20LBST Universal Satellite Modem Rear Panel Interfaces
MN-DMD20-20LBST Revision 14 5–26
5.12 Ethernet Data Interface (Optional)
The optional modem Ethernet Data Interface provides four RJ-45 10/100 Base-T interface. The
Ethernet interface supports Auto-Crossover and Auto-Sensing. The Ethernet port are referred to
as JS1 through JS4.
JS1 is Port 1
JS2 is Port 2
JS3 is Port 3
JS4 is Port 4
Refer to Figure 5-1 for outline drawings and Appendix J for setup & configuration.
The DMD20 & 20LBST supports Radyne HDLC and Comtech HDLC modes,
offering compatibility with the SLM5650A Bridge Interface.
5.13 HSSI / G.703
The HSSI (High-Speed Serial Interface) (J1) complies with the HSSI Functional and Electrical
Specifications. The physical interface is a 50-Pin SCSI-2 Type Connector. Electrical levels are
ECL. Gapped clocking not supported. The pinouts for this interface are listed in Table 5-14.
Table 5-14. J1 – HSSI (High-Speed Serial Interface) 50-Pin Connector
Pin No. (+)
Pin No. (–)
Signal Name
Description
Direction
1
26
SG
Signal Ground
---
2
27
RT
Receive Timing
Output
3
28
CA
DCE Available
Output
4
29
RD
Receive Data
Output
6
31
ST
Send Timing (SCT)
Output
7
32
SG
Signal Ground
---
8
33
TA
DTE Available
Input
9
34
TT
Terminal Timing (SCTE)
Input
11
36
SD
Send Data
Input
13 38 SG Signal Ground ---
14 - 18 39 – 43
5 Ancillary to
DCE
Reserved Input
19 44 SG Signal Ground ---
20 - 23 45 - 48
4 Ancillary
from DCE
Reserved Output
24
49
TM
Test Mode
Output
25
N/A
MOD_FLT
Alarm
Output
50
N/A
DMD_FLT
Alarm
Output
IMPORTANT