gould@theory.tn.cornell.edu (EWD) (04/04/91)
Greetings: I've come up with a use for my Sanyo MBC-1000 that requires a fairly good idea of the passage of time. Since it has no clock (or does it?), I was going to write myself characters at 300 baud with an isr to update a counter and start over (seemed like a good kluge at the time.) But looking at the schematic I saw an 8253-5 interval timer just sitting there doing nothing and was delighted to think I could do it right. So I can load the timer and read the contents, but I need to keep track of each time it times out timer 1, every half hour or so. It looks like this can be done by setting it up to generate an interrupt and incrementing a counter in memory, but I don't see how all this works by looking at the schematic. I can do it by polling the timer values in a keyboard-idle loop, but would prefer to try the interrupt route first. Can anybody give me a rundown on how to go about this? Thanks, Eliot Eliot W. Dudley edudley@rodan.acs.syr.edu RD 1, Box 66 Cato, New York 13033 315 437 0534