Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!rochester!dibble From: dibble@rochester.ARPA (Peter C. Dibble) Newsgroups: comp.sys.m6809 Subject: Re: COCO 3 problems Message-ID: <23404@rochester.ARPA> Date: Tue, 23-Dec-86 15:11:05 EST Article-I.D.: rocheste.23404 Posted: Tue Dec 23 15:11:05 1986 Date-Received: Tue, 23-Dec-86 22:44:04 EST References: <1986Dec15.155154.14868@utcs.uucp> Organization: U of Rochester, CS Dept., Rochester, NY Lines: 30 Summary: Guess: Software doesn't run a precise clock. In article <1986Dec15.155154.14868@utcs.uucp>, ac@utcs.uucp (Mark Acfield) writes: > > Subject: COCO 3 clock speed > ... paraphrased "I suspect that the CoCo3 has an inaccurate occilator." > I decided to check this out using the TIMER function built into basic. > The result of my experiment, which by this time came as no surprise, was > COCO 3 counts of 60 seconds in about 58 seconds or real world time. > ... > My little timer program is listed below (as well as I can remember it): > 10 TX=999 > 20 TIMER=0 > 30 ' > 40 T=INT(TIMER/60) > 50 IF T<>TX THEN PRINT T:TX=T:SOUND 100,1 > 60 GOTO 30 What's the ' in the basic program. Is the idea to see whether the program beeps in 999 seconds? I checked the accuracy of the CoCo 3's clock with the date t command in OS-9. It was losing less than half a second per minute. Since you found that several CoCo's were losing 2 sec per min in Basic and I got a different figure under OS-9, I'd guess that the problem is in software. Given that the CoCo3 has a countdown timer, that sounds like a good guess. See page 221 of the Tandy manual for the CoCo 3 where it says that TIMER returns a number that is incremented ROUGHLY every 60th of a second. Peter Dibble