And/or using a RTOS. I remember using a RTOS on a PIC16/18 family chip like ten years ago. But the most usual thing was knowing the precise timings that takes

And/or using a RTOS. I remember using a RTOS on a PIC16/18 family chip like ten years ago. But the most usual thing was knowing the precise timings that takes instructions and the peripherals to allow do multiple things at same time.