That program was an interesting read thank you. It certainly makes me think I should consider learning some assembly code, to allow me to control the number of cycles of time critical programs and also ensure that variables are saved in certain banks so the PIC does not need to spend time jumping from one bank to the other when running a critical task.

For the time being I will stick with DT-INTS as I believe writing my own assembly level interrupt is seriously beyond me. Maybe something to try in a few years.

I think I'll spend sometime adjusting the numbers being loaded into the various timer registers and see if I can learn some assembly code.

Thanks for your help