To fulfill customer expentations and fill out customer reports about the device, is there also one section about CPU Utilization. Because I have never done such task before I have overview some "Google Search" articles. A lot of the articles are in direct connection with Linux programming, a lot of them speak generally about CPU Utilization (just theoretical) and I didnt found no article about the method how can be this done .. okay there are some: embedded.com.
I am interested how YOU have done such task timing job before? I am intereseted in method and also whit which tool was done? With some direct measuring on the osciloscope (or logic analyser) or capturing data from osciloscope and post processing them? Which time frame to take for CPU Utilization to calculate - most "busy moment" when all interrupts are present, because in this case CPU utilization is much bigger then maybe 1 milisecond or 1 microsecond later, when only the background loop is executing?
Maybe for reference how I have made my first CPU Utilization approach (I don't know if is the right approach): Every interrupt when start executing have dedicated PIN which goes high when interrupt begin and gets low when interrupt ends. There is also same propagation delays involed. I export this signals over the osciloscope into one file and post-process with octave. There is still an issue which timeframe to take.
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