Pakscan IIE System Manual
84 of 132
Publication S177E V2.0 Issue 03/05
11.1 Jumper functions
Internally the PS410 has several jumpers used to configure the card to match the performance
required. Once the function has been set the next most important setting is the use of bias and
termination resistors on the RS485 highway. In general termination and biasing should only be fitted
once to any RS485 highway and it should be at the host connection end.
Jumper
Position
Function when fitted
J1
1-2
) Convert master station port 1 to RS232
4-6
)
7-8
)
2-3
) Convert master station port 2 to RS485
5-6
)
8-9
)
J2
1-5
Select baud rate 19200 ) Fit one only
2-6
Select baud rate 9600
)
3-7
Select baud rate 4800
)
4-8
Select baud rate 2400
)
J3
1-2
RS485 data line bias resistor
3-4
RS485 data line bias resistor
J4
1-2
RS485 data line termination resistor
J5
1-2
RS485 control line bias resistor
3-4
RS485 control line bias resistor
J6
1-2
RS485 control line termination resistor
J7
1-2
) 2-wire RS485 communications
7-8
)
or
or
3-4
) 4-wire RS485 communications
5-6
)
11.1.1 PS410 port 2 to RS485 setup
To use the PS410 to convert the master station RS232 port (port 2) to a second RS485 port.
Set J1 to positions 2-3, 5-6 and 8-9 (marked ’PORT 2 TO RS485’ on the PCB)
Set J2 according to the baud rate to be used
See Section 11.1.4 for details of setting J3, J4, J5 and J6
RS485 communications will use the ’Port 4’ connector on the back of the rack. Note that the
Port 2 connector can no longer be used.
Set J7 for either 2-wire or 4-wire RS485 communications.
This second RS485 port is isolated and has the same I/O connections as the master station port 1.
