8-Port RS422/485 Serial PCI Card
2
RS485 User: Since the factory jumper settings are initially set at
2-wire RS485 mode. There is no need to change any jumper
settings from the default settings.
RS422 User: Change the mode jumper away from the ”485”
position. Keep the other settings unchanged.
1.
Mode Jumpers:
Mode Settings for all S1~S8 Ports (JP1):
Jumper Name
Jumper Positions
Mode and Termination Resistor
Setting
S2H/S2L
S2L
(Default)
Reserved for Future Use. Please do
NOT change it.
ECHO/NO ECHO
ECHO
Transmitting data will be echoed
back
NO ECHO
(Default)
No echo data
S1H/S1L
S1L
(Default)
Reserved for Future Use. Please do
NOT change it.
422/485
485
(Default)
2-wire RS485 mode
422
4-wire RS422 mode
Please note that if the mode were set at “422” mode, the ECHO settings
will take no effect.
The Echo mode is useful for the application program to detect if the
RS485 bus were in a collision. If the echoed data was not equal to the
transmitted data, then the bus was in a collision.
2.
S1~S8 Termination Resistor Enable/Disable Jumpers
(JP4,JP6,JP8,JP10,JP5,JP7,JP9,JP11):
S2H
ECHO
S1H
485
3. Jumper Settings
S2L
NO ECHO
S1L
422
