mfs@edison.GE.COM (Synth Hacker @ Lost in the Mountains, Inc.) (09/23/88)
Lately, my 6 month old Amiga 500 has been doing strange things. Every now and then it will just reset itself and try to re-boot. I have kind of a minimal system; 1 floppy, 1/2 meg Commodore RAM expansion, an ECE MIDI interface, a modem and a monochrome monitor. I've tried unplugging the modem and MIDI interface and I checked to make sure all the chips were solidily seated, but every once in a while it still happens. Any clues ? Martin
mfs@edison.GE.COM (Synth Hacker @ Lost in the Mountains, Inc.) (09/27/88)
HELP! My A500 is reseting every now and then. This happens just like I had done it from the keyboard; no Gurus. Also, every now and then when I power it up, the caps lock LED flashes about once a second and the keyboard doesn't work. Usually, if I power it down and wait a while, I can bring it back up and the keyboard works OK. Even when the keyboard is out though, I can run MIDI stuff (with the mouse) so my serial port appears to be working (or maybe I just haven't caught it screwing up yet). I have been religiously unplugging all my computer and synth stuff at the hint of a thunderstorm, but like a fool I have been leaving my modem connected to the phone line. Could one of the 8520's have gotten 'warped' by a surge via the modem ? Is the keyboard handled by the 8520's or are there other chips that do this ? Has anybody had a similar problem ? Does anybody have any ideas ? Where can I get Amiga chips ? I called Kasara microsystems (they have an ad in computer shopper), but they are out of 8520's and can't tell me when they will get any in. If anybody can help me out, please e-mail. I have a project that is about 1/2 complete and the deadline is rapidly approaching! Martin
u563694848ea@deneb.ucdavis.edu (0040;0000009960;0;250;141;) (09/28/88)
I had that problem back when I owned a 500, and what fixed it was replacing the keyboard. Of course, that wasn't the only thing that ever broke on the 500... but it would take too long to tell that story! Anyhow, that sounds EXACTLY like what I had: blinking caplock, dead keyboard, everything else worked... I didn't have a modem then, so that probably isn't what caused it. Just thank the guys (guy?) at commodore's huge quality control plant...
kim@amdahl.uts.amdahl.com (Kim DeVaughn) (09/29/88)
In article <1651@edison.GE.COM>, mfs@edison.GE.COM (Synth Hacker @ Lost in the Mountains, Inc.) writes: > > My A500 is reseting every now and then. This happens just like I > had done it from the keyboard; no Gurus. Also, every now and then when > I power it up, the caps lock LED flashes about once a second and the > keyboard doesn't work. Usually, if I power it down and wait a while, > I can bring it back up and the keyboard works OK. > > Has anybody had a similar problem ? Does anybody have any ideas ? Yup ... I had identical symptoms on my 2000. First time it happened was about two months after I got it, and I thought it was a fluke, as it didn't recur for quite awhile. Anyway, it eventually got to the point where it was happening every 20 minutes or so, and I had discovered that if I unplugged/plugged the keyboard cable as soon as the led started flashing, I would (usually) avoid the crash, and all was well for another short period of time. Quite annoying ... One thing I finally noticed (once the frequency of occurance went up), was that when it *did* happen, I was (usually) typing pretty *hard* on the keyboard ... I started tapping chips on the keyboard board, but couldn't isolate it to any particular part or area. Finally, close inspection of the solder side of the board showed two really ugly joints. Both on the keyboard's oscillator crystal. In fact, the xtal leads were actually a bit loose inside the dull, gray, corroded looking joints. I resoldered these two leads, and poof! ... no more problems. Also, I put a small square of double-sided adhesive foam tape between the xtal and the board. Seems that I've heard that xtal's can generate minute mechanical/acoustic viberations, that can destroy solder joints over time, and I figured that the foam tape may help to dampen any such, if indeed they exist at all. Can't hurt, anyway, and at least the xtal is now firmly supported. So ... I'd start looking for a loose component and/or a bad solder joint on or around the keyboard. I can't say it'll be the xtal's leads, but I I'd sure start looking there! Good luck tracking *your* problem down ... intermittents can be a real bitch to find ... Hope this helps out. /kim -- UUCP: kim@amdahl.amdahl.com or: {sun,decwrl,hplabs,pyramid,uunet,oliveb,ames}!amdahl!kim DDD: 408-746-8462 USPS: Amdahl Corp. M/S 249, 1250 E. Arques Av, Sunnyvale, CA 94086 BIX: kdevaughn GEnie: K.DEVAUGHN CIS: 76535,25