AT Commands for GSM/GPRS Wireless Modems: Reference Guide
Source: Multi-Tech Systems
This document describes the AT-command based messages exchanged between an application and the Multi-Tech Systems, Inc. products in order to manage GSM-related events or services. In this document, the word "product" refers to any Multi-Tech product supporting the AT commands interface. Commands always start with AT (which means ATtention) and finish with a character.