Hi there,
Glad you got it working either way for you, However for anyone looking to work through this kind of problem, You could answer some basic questions, Which BSP were you using with the Xiao?
The interrupts require a certain amount of nuance and understanding to work properly, the Xiao eco system is NOT for everyone beginners and experts alike. It’s tiny size and powerful capabilities are not easily understood without additional exercise and knowledge of it’s Peripheral ports and operations, It’s NOT an 8-bit Atmel AVR not even close.
How was this powered?
You would benefit by it’s tiny footprint and low power draw especially if the Model is a small one. I suspect there was another issue afoot in relation to the questions. Props to liaifat85 for his code suggestion. There is also another thread of a Firetruck model with excellent GPIO sequencing for the realistic emergency lights and effects I would look that up and see if you can glean anything from the authors efforts.
Can you post a pic of it so we all can see your progress?
Thanks for the interesting comparison.
GL 
PJ
