Interrupt service latency is simply the time it takes between the interrupt request and the routine that services it. You have to account for it with any timing critical program.
hey guys thanks for the help so far...
can anyone help me with info on how to convert a sine wave to a square wave...cos i'm thinking of converting the power signal to a square wave and then using the Uc to measure the frequency...
Interrupt service latency is simply the time it takes between the interrupt request and the routine that services it. You have to account for it with any timing critical program.
Which only works if that is all the micro is doing. If you have multiple critical timings on interrupts the "account for it" is lost if one interrupts the other.
I still recommend capture registers for anything critical. That way the only thing you need to worry about is overflowing the counter twice before you service the interrupt. Of course I am used to designing for multiplexed displays, high speed frequency counting, heart rate counting, and a clock all running at the same time, sometimes more.
guys thanks a lot for all the help so far what about converting the power to a square wave then using the internal clock to measure it?(it seems like a nice simple idea)