(
ATtention command set) A series of machine instructions used to activate features on an analog modem. All cellular devices are required to support the AT commands as specified by the 3GPP.
Developed by Hayes Microcomputer Products and known as the Hayes Standard AT Command Set, it is used entirely or partially by most every modem manufacturer. AT is a mnemonic code for ATtention, which is the prefix that initiates each command to the modem. See
3GPP and
Hayes Smartmodem.