C9900-E210 with RS485 interface
The module for converting an RS232 interface of the motherboard into RS485 is led out via a 9-pin standard DSUB connector in a bracket. The interface is electrically isolated and protected by overvoltage protection. If an overvoltage occurs, the channel is switched off.
Fig.14: RS485 interface pin numberingPin | Signal | Type | Description |
|---|---|---|---|
1 | - | - | - |
2 | TxD + | Data-Out + | Transmit 485 |
3 | RxD + | Data-In + | Receive 485 |
4 | - | - | - |
5 | GND | Ground | Ground |
6 | VCC | VCC | +5 V |
7 | TxD- | Data-Out - | Transmit 485 |
8 | RxD- | Data-In - | Receive 485 |
9 | - | - | - |
On delivery the interface is configured as a half-duplex endpoint without echo as standard:
Function | Status |
|---|---|
Echo | off |
Auto send | on |
Always send | off |
Auto receive | on |
Always receive | off |
Termination | on |