How to handle multiple interrupts of the same clock rate?

[coryoryoh]

One of the first things any literature says about using interrupts is 'keep the code small'. I was wondering if there are rules of thumb regarding how much is too much to fit inside a callback function, and what to do when it is indeed too much.

My code has a callback function using the hardware timer that needs several if statements, writes to a digital pin, flips a boolean, and calculates a value after reading a value from a table in program memory. All of these separate items are timing-critical, and won't work outside of the callback function (I've checked).

at present, the code works. However, I'm about to add a lot more code and know that I'll have to deal with this sooner or later.

Can anyone recommend a method for handling timing-critical functions that are/may be too large to fit inside of one callback function?

Thanks in advance.

[Paul_KD7HB]

Interrupts are ALWAYS prioritized, so if by chance two or more occur at the identical time, the highest priority interrupt goes first, then the next, and so on...

[lastchancename]

First effort should be to ‘set a flag’, test a state, or ‘increment a counter’ in the ISR.
Then RETURN.

Later when the rush is over, process any accumulated events in your main() loop.

That main might get interrupted again, but you know your real-time stuff is being handled properly.