RS232 DB9 Null Modem Cable
Now available from PMD Way are these great value RS232 DB9 Null Modem Cables.
Null modem is a communication method to directly connect two DTEs (computer, terminal, printer, etc.) using an RS-232 serial cable.
The name stems from the historical use of RS-232 cables to connect two teleprinter devices to two modems in order to communicate with one another; null modem communication refers to using a crossed-over RS-232 cable to connect the teleprinters directly to one another without the modems.
It is also used to serially connect a computer to a printer, since both are DTE, and is known as a Printer Cable.