7
Before
opening the Model 590A/591A’s case, check the default control
signal settings (shown below). If the default configuration is correct,
move to Section 4.0 of this manual. Otherwise, proceed to section “Set-
ting the Internal Switches” to change the control signal settings.
3.2 SETTING THE INTERNAL SWITCHES
All switches and jumpers are located on the top side of the Model 590A
or Model 591A PC board. To access the PC board, open the case by
inserting a small flat-blade screwdriver in the slot on either side of the
case and twisting gently. Figure 1 shows the location of the DIP switches
on the circuit board.
Figure 1.
Model 590A/591A PC board, showing jumper locations and DTE/DCE Orientation
DCE Side
DTE Side
DTR (20)
(20) DTR
or
RTS (4)
(4) RTS
CD (8)
(8) CD
or
DSR (6)
(6) DSR
or
CTS (5)
(5) CTS
*NOTE: Default control signals are shown above in
bold italics
Control
Signal 1
Control
Signal 2
1 2 3
1
2
3
JP3
JP2
JP1
123456
7
8
ON
123456
7
8
ON
ON
ON
DCE
Side
DTE
Side
Connect to
“DTE”
Connect to
“DCE”
