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Null-modem cable is basically used for communication of two RS-232 "DTE" devices with each other. To create null-modem connection between the devices you need to use two computers or two serial ports of a single computer connected with null-modem cable. The both methods described above are expensive and difficult because of many reasons. The most reliable way to create null-modem connection is using of virtual serial ports emulated by virtual serial port driver and null-modem cable .....
