I need to generate a timed loop. I have read a lot about timed loops that are not really timed loops. i.e. they will have a number of tasks plus a pause time of say 10ms. Therefore, the total loop time is 10ms + the time taken to complete the tasks in the loop. In my mind this is not a timed loop as there is no knowledge or control over the timing of the loop. Is it possible to set the minimum time for a loop cycle?
Basically no.
In the arduino environment you also have interrupts going off to service the timers so any tru timed loop gets screwed up by that as well.
However doing a timed loop is totally the wrong thing to do period. There are other techniques to use and the chip has at least three internal timers to help you get very accurate and consistant results.
By the way 10 mS is way over the top for a loop overhead, more like 0.15uS.
Is it possible to set the minimum time for a loop cycle?
No.
You should make loop() execute as quickly as possible, and use millis() or micros() to record then and now, and do whatever timing critical item(s) need to happen when now minus then equals or exceeds the interval between events that you want to have.