Hayes command set

standard for controlling modems

Most dialup modems follow to a large extent the specifications of the Hayes Command Set, a specific programming language originally developed for the Hayes Smartmodem 300 baud modem. The modem initialization string consists of a series of commands. It prepares the modem for communications, setting such features as dialing mode (tone or pulse), waits, detection of the busy signal and many other settings. Newer modem communications programs reset the initializations string for users according to which menu options they have selected or according to the enabled features. With Windows or Macs, for instance, the user does not see or type these commands, or even know about them.
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