AVR-Chat

Normally no stepper motors works on speeds beyond 1 to
2 KHz. So you can do it in one of your timer overflow
interrupts.

Also, any reaction which may take place against
changing input signals, takes time. if this time could
be large enough you can sample it in another or same
timer routine.

other tasks could be broke into state machines to
achive maximum performance, but using a faster micro
may help you better.

good luck;


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