串口（RS232 DB,RS232/485,Internal RS232）
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Contents
RS232/Debug Port (COM2)
RSB-4680 can communicate with a host server (Windows or Linux) by using debug cable
RS232/485 (COM4)
RSB-4680 provides one D-Sub 9-pin connector serial communication interface port. The port can support RS-232/485 mode communication.
| Pin | Description |
| 1 | COM4_DCD_a/(UART4_TXD485#) |
| 2 | COM4_RX_a/(UART4_TXD_485P) |
| 3 | COM4_TX_a |
| 4 | NC |
| 5 | GND |
| 6 | NC |
| 7 | COM4_RTS |
| 8 | COM4_CTS |
| 9 | NC |
Internal RS232 (COM)
RSB-4680 provides 2 x internal 4 wires RS-232 ports with 5V/12V selection. (Refer to Jumper CN6).
| Pin | Description |
| 1 | COM6_TXD |
| 2 | COM6_RXD |
| 3 | COM6_RTS# |
| 4 | COM6_CTS# |
| 5 | COM6_PWR |
| 6 | GND |
| 7 | GND |
| 8 | COM7_PWR |
| 9 | COM7_CTS# |
| 10 | COM7_RTS# |
| 11 | COM7_RXD |
| 12 | COM7_TXD |
Internal RS232 (COM13)
RSB-4680 provides 2 x internal 4 wires RS-232 ports.
| Pin | Description |
| 1 | COM1_TXD |
| 2 | COM1_RXD |
| 3 | COM1_RTS# |
| 4 | COM1_CTS# |
| 5 | NC |
| 6 | GND |
| 7 | GND |
| 8 | NC |
| 9 | COM3_CTS# |
| 10 | COM3_RTS# |
| 11 | COM3_RXD |
| 12 | COM3_TXD |
