AT Command Tester
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Download AT Command Tester for 32-bit Java VM
Download AT Command Tester for 64-bit Java VM

How to check if you have 32-bit or 64-bit Java VM on your machine?
In Windows Command Prompt, type java -version
In above case, 32-bit Java VM is installed in the system. If 64-bit Java VM is installed, you'd see 'Java HotSpot(TM) 64-Bit Server VM' for the version command.

Version Changes

Version 27 Mar 16 2014 Add support for SMS PDU mode.
Version 26 Feb 2 2014 Improve UI responsiveness.
Add tutorial links for features
Version 25 Jan 27 2014 Remove AutoConnect option. This feature will be re-considered for future versions.
Version 24 Jan 13 2014 Added support for Huawei M2M modules.
Version 23 Nov 3 2013 Added diagnostics commands for SIMCOM M2M modules.
Easy connect option in 'Data Call' tab
Version 21 Oct 24 2013 Enhanced M2M software diagnostic features.
Version 20 Oct 16 2013 Added a AutoConnect option. AT Command Tester will detect and connect to modem ports automatically.
Version 19 Oct 8 2013 Add support for Quectel M2M modules.
Easy test of Quectel TCP/UDP, HTTP M2M software features
Quectel HTTP GET script.
Version 18 Sept 3 2013 Improved interace - Consolidated output window.
Clear and save contents from the output window.
Version 17 Aug 28 2013 Add scripts for Simcom M2M modules in the 'Script Mode' tab
Test HTTP, FTP, TCP, GPS M2M software features using AT Command Scripts.
Version 16 Aug 25 2013 Add WAIT command in script mode.
Add scripts for Telit M2M module featues
Version 15 Aug 16 2013 Add support for Telit M2M module features such as TCP/UDP, HTTP, FTP, GPS, Email etc.
Version 14 July 21 2013 Add support for posting in the forum from AT Command Tester