串行直连电缆9针-9针(NullModem)引脚定义图

串行直连电缆9针-9针(NullModem)引脚定义图

串行直连电缆用于两台计算机的直接相连，电缆两端的插头都是 9 针母插头：

引脚定义

	D-Sub 1	D-Sub 2
Receive Data	2	3	Transmit Data
Transmit Data	3	2	Receive Data
Data Terminal Ready	4	6+1	Data Set Ready + Carrier Detect
System Ground	5	5	System Ground
Data Set Ready + Carrier Detect	6+1	4	Data Terminal Ready
Request to Send	7	8	Clear to Send
Clear to Send	8	7	Request to Send