Hi,Shamir

Answering your question, Assembler interrupts have a small latence time ... Microchips tells "around" 4 clock cycles in its datasheets and midrange manual.

this gives one assembler instruction time ... two, if pessimistic !!!

Now, the good question is to know EXACTLY what needs to be saved ( and restored after ... ) THIS portion of code always take some time, and even need some timing values to be corrected in a further step.

Darrel's "instant Interrupts" is the easiest way to care with interrupts "headache" ... but just takes MINIMUM time - Only MINIMUM !!!

Alain