11
Seriell RS
-
422/485 PCI Board
English
This jumper is to set the transmission data will be echoed back or not. The Echo
mode is useful for the application program to detect if the RS485 bus has collision. If
the echoed data was not equal to the transmitted data, then the bus was in a colli-
sion. This setting only affects the RS485 2
-
wire mode. It doesn
’
t affect RS485 4
-
wire, RS422, and RS232 modes.
2. Termination Resistor Enable/Disable:
OFF ON
OFF
=
Termination Resistor Disabled
(Default)
ON
=
Termination Resistor Enabled
This jumper enables/disables the 120 Ohm termination resistor between DATA+ and
DATA
-
of the RS485 transceiver:
JP7 for S1 Port
JP8 for S2 Port
3. Echo or No Echo Settings:
JP3 for S1 Port
JP4 for S2 Port
OFF ON
OFF
=
No Echo Data
(Default)
ON
=
Transmission data will be echoed
4. TXD Control Setting:
This jumper is used to select the control signal for the transmitter buffer in RS485 2
-
wire mode. There are 2 settings are selectable, one is
“
MAN
”
(manually) the other
one is
“
AUT
”
(automatically, factor default), please keep it at
“
AUT
”
in all cases.
MAN AUT
AUT
=
TXD Control is Automatic
(Default)
ON
=
TXD Control is Manual
(Needs to be Configured Manually in the Device Manager)
JP1 for S1 Port
JP2 for S2 Port
5. Factory Use Only Connectors (J1):
This connector is only used for factory production purpose, please don
’
t install any
jumper or cable on it!
