3Com NETBuilder II Installation Manual page 9

Cabling the HSSI Module for Network Connection
A SCSI-type cable connects the HSSI Module DTE connector to a Data Service Unit (DSU).
Table 1-1 describes the connectors. Table 1-2 describes the pin assignments.
3Com recommends using minimum lengths of this cable, especially if you plan to use these
serial lines at high speeds. The maximum cable length allowed is 50 feet.
To connect the HSSI module to the network, insert a SCSI type cable into the female connector
in the rear of the HSSI module
Table 1-1. Connectors
Connector
Plug connector type
Receptacle type
Table 1-2. HSSI Adapter Cable Pinouts
Signal Name
Signal Ground
Receive Timing
DCE Available
Receive Data
Loopback Request
Send Timing
Signal Ground
DTE Available
Terminal Timing
Loopback Circuit A
Send Data
Loopback Circuit B
Signal Ground
5 ancillary to
DCE
Signal Ground
5 ancillary from
DCE
Signal Ground
Description
2 row, 50 pin, shielded tab connectors,
AMP plug part number 749111-4 or equivalent
AMP shell part number 749193-2 or equivalent
2 row, 50 pin, receptacle header with rails and latch blocks,
AMP part number 749075-5 or equivalent
Mnemonic Pin Number
(+ side)
SG 1
RT 2
CA 3
RD 4
LC 5
ST 6
SG 7
TA 8
TT 9
LA 10
SD 11
LB 12
SG 13
14 - 18
SG 19
20 -24
SG 25
Installation
Installing the HSSI Module
Pin Number Direction
(- side)
26 --
27 in
28 in
29 in
30 in
31 in
32 --
33 out
34 out
35 out
36 out
37 out
38 --
39 - 43 out
44 --
45 - 49 in
50 --
1-5