AT an abbreviation for Attention are the commandsused to control MODEMs. These commands come fromHayes commandsthat were used by the Hayes smart modems. The Hayes commands started with AT to indicate the attention from the MODEM. The dial up and wireless MODEMs (devices that involve machine to machine communication) need AT commands to interact with a computer. These include the Hayes command set as a subset, along with other extended AT commands.
AT commands with a GSM/GPRS MODEM or mobile phone can be used to access following information and services:
1. Information and configuration pertaining to mobile device or MODEM and SIM card.