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Digi TransPort® WR21 Installation Guide
Appendix A: SERIAL 0 Port Pin-out Diagram
WWAN
SECONDARY
LAN 0 | LAN 1 |
RS232
SERIAL 0
Pin 1
Pin 9
SERIAL 0
WWAN PRIMARY
2A MAX
Pin # | Direction | RS232 DCE | Description |
|
|
|
|
1 | Out | DCD | Data Carrier Detect |
2 | Out | RXD | Receive Data |
3 | In | TXD | Transmit Data |
4 | In | DTR | Data Terminal Ready |
5 | N/A | GND | Ground |
6 | Out | DSR | Data Set Ready |
7 | In | RTS | Ready To Send |
8 | Out | CTS | Clear To Send |
9 | Out | RI | Ring Indicate |
RS422/ RS485 |
|
|
Pin # | Direction | RS422/ | Description |
|
| RS485 |
|
1 | Out | CTS_B | Clear To Send B |
2 | Out | RD_A | Receive Data A |
3 | In | TD_A | Transmit Data A |
4 | In | RTS_B | Ready To Send B |
5 | N/A | GND | Ground |
6 | Out | RD_B | Receive Data B |
7 | In | RTS_A | Ready To Send A |
8 | Out | CTS_A | Clear To Send A |
9 | In | TD_B | Transmit B |
Notes:
For true RS485 mode
The CTS and RTS signals for optional and not normally needed for RS485.
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