1 Introduction 1.1 Scope of the document This document presents the AT Command Set for SIMCom SIM800 Series， including SIM800V， SIM840V， SIM800W， SIM840W， SIM800W16， SIM840W16， SIM800L， SIM800H， SIM800， SIM800M64， SIM800G， SIM808， SIM800C， SIM800A， SIM800F， SIM800C-DS and SIM868. 1.2 Related documents You can visit the SIMCom Website using the following link： http://www.simcomm2m.com 1.3 Conventions and abbreviations In this document， the GSM engines are referred to as following term： ME （Mobile Equipment）; MS （Mobile Station）; TA （Terminal Adapter）; DCE （Data Communication Equipment） or facsimile DCE （FAX modem， FAX board）; In application， controlling device controls the GSM engine by sending AT Command via its serial interface. The controlling device at the other end of the serial line is referred to as following term： TE （Terminal Equipment）; DTE （Data Terminal Equipment） or plainly “the application” which is running on an embedded system;