Calculating how many T states of instructions you could in get during flyback?
Not quite.
Timing how long each interupt cycle could have on the CPU with the total amount of time allowed for all interupts being 60 mSecs,with the remaining time running the controlling program.
music was a set one, keyboard/joystick scanning was a set time, and animation being a set time.... however , there was a subtle bug that ment somewhere in there the processing time for all interupts rose to 70mSec, which was beyond the 65 mSec main interupt............. so the interupts would arrive before the previous one had finished.. and then the stack would grow very fast and wipe the memory before I could even get a debugger in there.
And of course, it would never happen on a single static run of each interrupt routine.
Ended up having to work out how many clock cycles each path through the code was using... aarrrrrrrrrrrrrrrghhhhhhhhhh.
Still... stood me in good stead for passing the open universities "M301: Concurrent and distributed systems design" module ... a course that was feared when it was introduced... [woah]
Bill
<<is far smarter than he first appears [alien]