查看“EMB-4922-COM”的源代码

[[文件:EMB-4922-COM.jpg|600px|缩略图|EMB-4922-COM]]
===== COM2： =====
:{| class="wikitable"
|-
! 信号名称 !! Pin !! Pin !! 信号名称
|-
| DCD || 1 || 2 || DSR
|-
| SIN || 3 || 4 || RTS
|-
| SOUT || 5 || 6 || CTS
|-
| DTR || 7 || 8 || RI
|-
| GND || 9 || 10 || GND
|}

* COM2 跳线功能设置（J5，J6，J8）：
:{| class="wikitable"
|-
! COM2 !! AS RS232 PORT !! COM2 !! AS RS422 PORT !! COM2 !! AS RS485 PORT
|-
| J5 || 1-3,2-4 || J5 || 3-5,4-6 || J5 || -------
|-
| J6 || 1-3,2-4 || J6 || 3-5,4-6 || J6 || 3-5,4-6
|-
| J8 || 1-2 || J8 || 3-4 || J8 || 5-6 7-8
|}

''' 当COM2设置为RS485/RS422/ RS232时，其管脚定义分别如下： '''
:{| class="wikitable"
|-
! RS485 !! RS422 !! RS232 !! Pin !! Pin !! RS232 !! RS422 !! RS485
|-
| DATA- || TX- || DCD || 1 || 2 || DSR || NC || NC
|-
| DATA+ || TX+ || RXD || 3 || 4 || RTS || NC || NC
|-
| NC || RX+ || TXD || 5 || 6 || CTS || NC || NC
|-
| NC || RX- || DTR || 7 || 8 || RI || NC || NC
|-
| GND || GND || GND || 9 || 10 || GND || GND || GND
|}