ARM Cortex-M3 vs.M0 Debugging (Can’t Monitor Task States) Using IAR C-SPY

**Apologies for the misleading title – the processors in question are a Cortex-M4 vs. Cortex-M3. ** I’m using the OpenRTOS IAR plugin to debug a project that uses both a dual-core Cortex-M4 (LPC 43xx) and M3 (LPC17xx), both running FreeRTOS. On the M4 I can monitor task states using the plug-in. However, on the M3 I don’t see the same information. I did not notice anything noticeable differences in the FreeRTOS configuration files that would prevent me from monitoring the task states. Am I missing something? Is this a difference between FreeRTOS versions? The plug-in details are as follows: OpenRTOSPlugin.dll v3.0.0 by WITTENSTEIN high integrity systems (both processors) The IAR EW version is as follows: IAR Embedded Workbench IDE – ARM 7.80.1 (both processors) The FreeRTOS versions are as follow: Cortex-M4 tskKERNELVERSIONNUMBER “V8.0.1” Cortex-M3 tskKERNELVERSIONNUMBER “V9.0.0” Thanks, Cory H.

ARM Cortex-M3 vs.M0 Debugging (Can’t Monitor Task States) Using IAR C-SPY

Are you using the M3 and M0 cores separately – one at a time – or is this a dual core device and you are debugging both at once? If separately then I am not aware of any reason why it would work with one and not the other. If together at the same time then I don’t think the plug-in will support that.

ARM Cortex-M3 vs.M0 Debugging (Can’t Monitor Task States) Using IAR C-SPY

They are used seperately and not a dual-core device (even though the M4 is a dual-core device, we are only running 1 core). Each processor has its own IAR project and seperate set of application code. I have tested running them both at the same time and independently (essentially with the M4 powered down and just running the M3 project) and experience the issue. Please see the attached image that demonstrates the missing Task State column.

ARM Cortex-M3 vs.M0 Debugging (Can’t Monitor Task States) Using IAR C-SPY

Perhaps it is something to do with a difference in the FreeRTOSConfig.h files – but I’m guessing. The plug-in determines the FreeRTOSConfig.h settings by attempting to read various different values from the task control block when it first connects. Values that are excluded from the build because of a FreeRTOSConfig.h setting return an error when the plug-in tries to read them, and the error is visible in the IAR output window. The errors will only show once per debug session, the first time the plug-in is used for that session, as once the plug-in knows the values don’t exist it won’t attempt reading them again. Do you see these error messages when you start a debug session – are there any differences in the messages output between the working and non-working projects?

ARM Cortex-M3 vs.M0 Debugging (Can’t Monitor Task States) Using IAR C-SPY

I did not see any error messages pertaining to my problem in the Debug Log window unfortunately. Attached is the output from running both debug sessions. I can include the FreeRTOSConfig files for your convenience, but I will have to create a few different posts.

ARM Cortex-M3 vs.M0 Debugging (Can’t Monitor Task States) Using IAR C-SPY

Non-working FreeRTOSConfig.h (M3) attached.

ARM Cortex-M3 vs.M0 Debugging (Can’t Monitor Task States) Using IAR C-SPY

Working FreeRTOSConfig (M4) attached.

ARM Cortex-M3 vs.M0 Debugging (Can’t Monitor Task States) Using IAR C-SPY

I think you will have to contact WITTENSTEIN high integrity systems, who maintain the plug-in, to see if they can ascertain the cause.

ARM Cortex-M3 vs.M0 Debugging (Can’t Monitor Task States) Using IAR C-SPY

Thanks for taking the time to look into this. I’ll contact them and see what they think of the problem.