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Am I only one that thinks that the PIT interrupt has the same nature as the Periodic interrupt of the RTC?
I was going to move my delay timing from the PIT to the RTC Periodic interrupt and use the PIT solely for Task switching.
Also instead of reading the CMOS Clock and Date info on every PIT interrupt I'm going to Use the Update Interrupt in the RTC which fire everytime it updates the time i.e once every 1/1024 sec.
I'm trying to increase interrupt response time.
How do you guys combine the RTC and PIT?

one of the difference you might encounter is the priority level. While PIT irqs virtually precedes everything else, the RTC interrupt may be deferred until keyboard, mouse, hard disk, network, etc. irqs have been processed. I'm not sure, but it will probably mean that you could be less confident about how much time elapsed since the timer event occured and the moment where your code is executed ...