Null modem pinout(laptop pc with usb communicate with destop pc(with DB9 com port)):2-TXD(yellow), 3-RXD(orange),5-GND(GND), 7-CTS(green),8-RTS(brown), 1/4/6/9-NC
This is DB9 Pinout , Please keep your attention special, the cable's TXD,it reflects to RXD of device, The cable's RXD,It reflects to TXD of device, CTS reflects RTS of device, RTS Reflects CTS of device.
USB to Null Modem serial adapter corrects DTE/DCE conflicts without requiring additional adapters or cables
USB to Null Modem (Cross-Wired) RS232 Serial Adapter, Support Win7/8/10/2000/XP/ANDROID/VISTA/WINCE/LINUX