>Well, that won't cause any problems -- the CIA timer (the interrupt timer) >runs in continuous mode. So although there might be some little fluctuations, >after 1000 interrupts the TI$ counters will have been incremented 1000 times. >(Kind of like the way the AC line is only 60Hz or 50Hz on average). On the >other hand, I think the tape routines change the IRQ vector, and of >course anything that changes the timer value or skips the update will >mess up the clock. Tape definitely does dork with the IRQ vector. >Let's see now... the interrupt timer uses a latch value of 17045. This >means an interrupt takes place every > > 17046 cycles * 14/14318181 sec/cycle = 0.0166672 seconds ^^^^^ ? Just a typo? >So, TI seems to stay pretty accurate (I always had it in my head that >it wasn't). TI$ is really easy to use, also. The TOD's latching makes things a little tricky -- and Jim Butterfield has mentioned how perverse setting it can be. I'm lazy, on top of all that. -- Cameron Kaiser *** http://calvin.ptloma.edu/~spectre/ *** spectre@ptloma.edu "Please dispose of this message in the usual manner." -- Mission: Impossible - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tcm.hut.fi.
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