AnsweredAssumed Answered

P&E Debugger Not Working After Low Power Mode

Question asked by Patrick Johnson on Mar 6, 2017
Latest reply on Mar 19, 2017 by Alice_Yang

I am having trouble using the P&E debugger (Multilink Universal FX) with a K20FN1M0 after the device has entered and exited a low power mode (VLLS1 to be specific).  Here is what I am trying to do...


  1. The device enters the low power mode.  I am using the Processor Expert call Cpu_SetOperationMode(DOM_STOP, NULL, NULL);
  2. The device restarts after a period with the LPTimer wakeup.


This all works just fine.  However, after having entered the VLLS1 state, I can no longer use the debugger.  Here is the scenario...


  1. Device is in VLLS1 or back to normal run mode (I can keep it from re-entering VLLS1 via a GPIO input).
  2. Connect the debugger to the target.
  3. Run the Debug command in Kinetis Design Studio.


The target runs (I have an LED that flashes), however I have no debugger action. In the "Debug" window, I have..

   Thread #1 <main> (Suspended: User Request)

      __vect_table() at 0x0



The only way to get out of this is power cycle the target.  This is fine on the bench, but in my application, I am not able to power cycle the device.  I can reset the device, but this does not fix the problem.  I have checked my version of P&E debugger pluggin and it is the latest...


Has anyone else seen this behavior, and is there a solution to recovering debugger functionality without power cycling the device?