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Information in this knowledgebase article applies to:

  • MDK-ARM V4.14, V4.20
  • MDK-ARM V4.21 through V4.70a
  • SmartFusion devices


The RTX_BLINKY example project for the Actel SmartFusion boards (A2F-EVAL-KIT and A2F-DEV-KIT) hangs after executing the os_sys_init function. This worked properly in V4.13a.


SmartFusion devices do not support the LDREX and STREX instructions of the Cortex-M3 which the os_sys_init function uses. SmartFusion2 devices do support these instructions, so the following solution only applies to SmartFusion devices.


For MDK-ARM V4.14 and V4.20

The attached files correct the problem using RTX on Actel SmartFusion devices. To install the files, do the following:

  1. Download the attached .ZIP file
  2. Extract the 2 files to your [Installation_Path]\ARM\RV31\LIB\ folder. [Installation_Path] is where you installed your MDK-ARM tools. The default is: C:\KEIL\.
  3. Rebuild your project.

For MDK-ARM V4.21 through V4.70a

For these versions, do not download the attached files. You already have the library file you need. Just direct µVision to include the RTX_CM3X.lib library which supports your Microsemi device. To do this:

  1. Open your µVision project
  2. In the Project Window, right-click the group folder that contains the RTX_Conf_CM.c file, and select Add Files to Group.
  3. Browse to the C:\Keil\ARM\RV31\LIB\ folder and select the RTX_CM3X.lib library, then click the Add button.
  4. Rebuild your project.

Your project will debug properly now.


This will be corrected in a subsequent release of MDK-ARM.



Request the files attached to this knowledgebase article.

Last Reviewed: Tuesday, March 19, 2013

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