12
11
3.2.1 REAR CARD JUMPER SETTINGS
Figure 6 (below) shows jumper locations for the four rear card
options. These jumpers determine various grounding characteristics for
the RS-232/V.35.
Figure 7 (below) shows the orientation of the rear interface card
jumpers. The jumper can either be on pegs 1 & 2, or on pegs 2 & 3.
Table 3 (below) provides an overview of interface jumper functions
for the rear interface cards. Following this overview is a detailed
description of each jumper’s function.
DTE Shield & Frame Ground (JB3)
In the connected position, this jumper links DB-25 pin 1 (M/34 pin
A) & frame ground. In the open position, pin 1(pin A) is “lifted” from
frame ground.
JB3
Position 1&2 = DTE Shield (DB-25 Pin 1 or M/34 Pin A)
and FRGND Connected
Position 2&3 = DTE Shield (DB-25 Pin 1 or M/34 Pin A)
and FRGND Not Connected
Signal Ground & Frame Ground (JB4)
In the connected position, this jumper links DB-25 pin 7 or M/34
pin B (Signal Ground) and frame ground. In the open position, pin 1
(or pin B) is “lifted” from frame ground.
JB4
Position 1&2 = SGND (DB-25 pin 7 or M/34 pin B)
and FRGND Connected
Position 2&3 = SGND (DB-25 pin 7 or M/34 pin B)
and FRGND Not Connected
Figure 6. Rear card jumper locations
JB4
JB3
Figure 7. Orientation of interface card straps
1
2
3
1
2
3
1
2
3
REAR CARD STRAP SUMMARY
Strap
Function
Position 1&2
Position 2&3
JB3
DTE Shield (Pin1) & FRGND
Connected
Open*
JB4
FRGND & SGND
Connected
Open*
Table 3. Summary of Strap Settings, * Indicates Factory Default
1 2 3
3
2
1