Rs485/422 Connector; Connection Of Rs485 Connector; Technical Specification Of Rs232 And Rs485; Connection Of Rs422 Connector - Advantech SmartFlex SR304 Hardware Manual

3. Router Design
The board allows for the selection between RS485 and RS422 interfaces, which can be configured
using jumpers. For guidance on configuring the jumpers, refer to the instructions printed directly on the
board. Additionally, the termination resistor can be enabled on the port board using a jumper; note that the
termination resistor is integrated into the port board itself.
The default configuration is set to RS485 with the termination resistor turned off.

Connection of RS485 connector:

Pin
1
2
3
4

Connection of RS422 connector:

Pin
1
2
3
4
Technical specification of RS232 and RS485 bus:
RS232 and RS485 interface
Max. operating RS232 bus current
Max. number of devices on RS485 bus
Max. output current on RS485 bus
Max. data rate
Max. total cable length (300 Bd, 200 nF/km)
SmartFlex SR304 Hardware Manual
Figure 44: RS485/422 connector
Signal Description
TxRx+ RS485 B (+)
TxRx- RS485 A (-)
TxRx+ RS485 B (+)
TxRx- RS485 A (-)
Table 22: Connection of RS485 connector
Signal Description
RxD+ RS422 (+)
RxD- RS422 (-)
TxD+ RS422 (+)
TxD- RS422 (-)
Table 23: Connection of RS422 connector
Table 24: Technical specification of RS232 and RS485
3.10 Interfaces Description
Direction
Input/Output
Input/Output
Input/Output
Input/Output
Direction
Output
Output
Input
Input
15 mA
32
60 mA
230400 bps on RS232
230400 bps on RS485
RS232 20 m, RS485 1200 m
29