Origin
Originally, the RS-232 standard was developed and used for teleprinter machines which could communicate with each other over phone lines. Each teleprinter would be physically connected to its modem via an RS-232 connection and the modems could call each other to establish a remote connection between the teleprinters. If a user wished to connect two teleprinters directly without modems (null modem) then they would crosslink the connections. The term null modem may also refer to the cable or adaptor itself as well as the connection method. Null modem cables were popular means of transferring data between the early personal computers in the 1980s and early 1990s.
Read more about this topic: Null Modem
Famous quotes containing the word origin:
“The essence of morality is a questioning about morality; and the decisive move of human life is to use ceaselessly all light to look for the origin of the opposition between good and evil.”
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