Writing code for embedded applications can be difficult. There are all sorts of problems you can run into – race conditions, conflicting peripherals, unexpected program flow – any of these can cause havoc with your project. One thing that can really mess things up is if your microcontroller is getting stuck on a routine – without the right debugging hardware and software, this can be a tricky one to spot. [Terry] developed a microcontroller load meter just for this purpose.
It’s a simple setup – a routine named loadmeter-task on the microcontroller sends a train of pulses to a mechanical ammeter. The ammeter is then adjusted with a trimpot to read “0” when the chip is unloaded. As other tasks steal CPU time, there’s less time for loadmeter-task to send its pulses, so the meter falls to the left.
Overall it’s a quick and easy bit of code you could add to any project with a spare GPIO pin, that might help you debug. Plus it’s cool to know how hard your project is pushing the silicon.