[STM32F205] MCU is doing a lot more work since last firmware, how to I debug ?

[root]

Posted on June 08, 2012 at 11:03

Hello,

I'm having a strange issue ... when I upgrade from firmware X to firmware Y, the MCU is consumming more amps (board consumption from 50mA to 80mA), and generates more heat (from 42°C to 50°C).

I checked a hundred time the differences in code, and cannot see any reason for this. Application is still running fine though ...

Any clue on how to debug this ? I'm using TASKING and I have ST Link V2 probes and SEGGER probes at hand.

Thomas.

[Tesla DeLorean]

Posted on June 08, 2012 at 13:47

With that much current I'd be looking very carefully at what the GPIO ports were doing. If there were some issues with AF settings, or pins fighting. Or generally what the GPIOs were driving, especially if the current if for the system, rather than just the CPU.

Presumably you've compared the entire source trees with merge tools like WinMerge or Araxis Merge, etc.

The other trick might be to build an intermediate firmware where you pull some subset of the changes and see at what point the current usage changes.