Specifications

SIM900 AT Commands Set
SIM900_ATC_V1.01 4 23.06.2010
Contents
Version History .................................................................................................................................3
1 Introduction..................................................................................................................................10
1.1 Scope of the document..........................................................................................................10
1.2 Related documents ................................................................................................................10
1.3 Conventions and abbreviations .............................................................................................11
1.4 AT Command syntax .............................................................................................................11
1.4.1 Basic syntax ................................................................................................................... 11
1.4.2 S Parameter syntax.........................................................................................................12
1.4.3 Extended Syntax.............................................................................................................12
1.4.4 Combining AT commands on the same Command line.................................................12
1.4.5 Entering successive AT commands on separate lines.....................................................12
1.5 Supported character sets........................................................................................................12
1.6 Flow control ..........................................................................................................................13
1.6.1 Software flow control (XON/XOFF flow control).........................................................13
1.6.2 Hardware flow control (RTS/CTS flow control)............................................................14
2 AT Commands According to V.25TER.......................................................................................15
2.1 Overview of AT Commands According to V.25TER ............................................................15
2.2 Detailed Description of AT Commands According to V.25TER ...........................................16
2.2.1 A/ Re-issues the Last Command Given.......................................................................16
2.2.2 ATA ANSWER AN INCOMING CALL ....................................................................16
2.2.3 ATD Mobile Originated Call to Dial A Number..........................................................17
2.2.4 ATD> <n> Originate Call to Phone Number in Current Memory...............................19
2.2.5 ATD> <str> Originate Call to Phone Number in Memory Which Corresponds to Field
<str> ........................................................................................................................................21
2.2.6 ATDL Redial Last Telephone Number Used...............................................................23
2.2.7 ATE Set Command Echo Mode ..................................................................................24
2.2.8 ATH Hang Up A Call ..................................................................................................24
2.2.9 ATI Display Product Identification Information .........................................................25
2.2.10 ATL Monitor speaker loudness..................................................................................25
2.2.11 ATM Monitor Speaker Mode ....................................................................................26
2.2.12 +++ Switch from Data Mode or PPP Online Mode to Command Mode ..................26
2.2.13 ATO Switch from Command Mode to Data Mode....................................................26
2.2.14 ATP Select Pulse Dialing...........................................................................................27
2.2.15 ATQ Set Result Code Presentation Mode..................................................................27
2.2.16 ATS0 Set Number of Rings before Automatically Answering the Call.....................28
2.2.17 ATS3 Set Command Line Termination Character .....................................................28
2.2.18 ATS4 Set Response Formatting Character ................................................................28
2.2.19 ATS5 Set Command Line Editing Character.............................................................29
2.2.20 ATS6 Set Pause before Blind Dialing .......................................................................29
2.2.21 ATS7 Set Number of Seconds to Wait for Connection Completion..........................30
2.2.22 ATS8 Set Number of Second to Wait for Comma Dial Modifier Encountered in Dial
String of D Command .............................................................................................................30