Null Modem Cable Pinout (DB9-DB25)

Use this cable between two DTE devices (for instance two computers).

	DB9 pin D-SUB female to PC1
	DB25 pin D-SUB female to PC2

	DB9	DB25
Receive Data	2	2	Transmit Data
Transmit Data	3	3	Receive Data
Data Terminal Ready	4	6+8	Data Set Ready + Carrier Detect
System Ground	5	7	System Ground
Data Set Ready + Carrier Detect	6+1	20	Data Terminal Ready
Request to Send	7	5	Clear to Send
Clear to Send	8	4	Request to Send

Note: DSR & CD are jumpered to fool the programs to think that they are online.

Our software allows you monitor, log, debug and test your RS232 or COM ports.