AnsweredAssumed Answered

Help to debug VCOM+FreeRTOS example on KDS

Question asked by Javier Soriano on Oct 28, 2016
Latest reply on Dec 14, 2016 by xiangjun.rong

Dear all, 


I modified the code from the VCOM + FreeRTOS example from the SDK. 


My setup:

FRDMK82f   --> usb --> Win7 PC --> Virtualbox --> Ubuntu14.04 --> Kinetis DesignStudio


I am able to communicate with the CDC device when I program the board using JLinkEXE.

I am also able to start the debugging from KDS. In other words, I see that the 'main' starts to run. 

I have also installed the FreeRTOS Task Aware Debugger for GDB.


The difference I see is that the VCOM device cannot connect to the virtual machine when in debugging mode. The USB device is reported as "busy". I read somewhere on the net that this may be the result of some MPU protection. But no more details on why or where to change this. I am also not sure if there could be another setting that stops me from using the VCOM device in a normal way when debugging. 


I cannot test my application without communicating with the VCOM device. 

Any pointers will be greatly appreciated.




EDIT: In order to discard the effects of using a virtual machine, I am now testing on a laptop that has Ubuntu 14.04 installed. My observations are pretty much the same. In other words, when running the application without a debugger, I can communicate with the CDC VCOM device. However when I try to open the same device while in debug mode (in Kinetis design studio), the VCOM device is simply not reported. 


dmesg says : "device not accepting address N, error -32"