RIP100.THD (c)1988 Golden Triangle, Inc. (c)1989 Wilson Van Alst Fm: Christopher Zach To: ALL About 6 months ago, my old M100 finally committed computer suicide. The screen comes up when I turn it on, but the clock doesn't work, and the first 3 characters on the screen are junk chars (always changing). Any ideas what could be wrong? I really miss the thing (TMPC is so nice), and want to either fix or replace it. =+=+=+=+=+= Fm: Tony Anderson To: Christopher Zach It's possible the clock chip died. If that's the case, the computer may be fully usable without it, since the "clock" part is separate from the "compute" part. - The first three characters should be the month indication, Jan, Feb, etc. Is that what you're saying is constantly changing? If that's the case, it might indicate a problem with the clock chip, since the data from the clock is loaded into a holding buffer every so often by a ROM routine. If the data is "changing" that would indicate the clock is changing. Maybe. =+=+=+=+=+= Fm: Christopher Zach To: Tony Anderson Tony: Interesting thought. The problem is the clock never 'ticks', but the first 3 chars change about twice a second. The chars that the M100 displays, however, are always "garbage chars (looks like something you see with the code key pressed). Meanwhile, the computer is 99% locked up. I say 99% because every once in a while, striking a key causes the computer to actually do something (like go into basic). =+=+=+=+=+= Fm: Tony Anderson To: Christopher Zach Sounds like a repair call, to me. But maybe some of the others can come up with something useful. =+=+=+=+=+= Fm: Christopher Zach To: Tony Anderson If I were to send this thing to Radio shack, they would probably laugh till their socks fell off (it has a LOT of miles on it). Besides, I can probably pick another one up for less money... =+=+=+=+=+= Fm: Tony Anderson To: Christopher Zach That is often the case... it's cheaper to get a used replacement, than it is to fix a problem machine. Especially since they seem to have the "replacement" mentality. (They don't "fix it", the replace whole boards.) =+=+=+=+=+= Fm: Gene Nestro To: Christopher Zach Did you COLD START it? Did you turn the MEMORY switch to off (on bottom of M100) and let it sleep for 24 hor 24 hours? Are the batteries fresh? =+=+=+=+=+= Fm: Christopher Zach To: Gene Nestro Yes, I did cold start, and I left the memory off switch off for 3 months. I use the power adapter, and I tried a spare one. No luck. It is one really wierd problem because when I cold start, it DOES check memory, and brings up the main screen. Also, if I press a key many times, it moves the bar or puts the key value in the display. I am totally stumped on this one. Pardon me if my message is a format disaster, but I am typing on a silent 700 at work (Ug). =+=+=+=+=+= Fm: Gene Nestro To: Christopher Zach Chris, my next step(s) would be: 1. replace AA batteries 2. completly discharge Nicads a. if you can enter Basic type POWER CONT b. stop rite there - leave 100 ON c. go to bed d. next AM enter Basic e. type POWER 100 =+=+=+=+=+= Fm: Christopher Zach To: Gene Nestro No dice. The 100's nicads were completely dead when I took it out of hiding yesterday. The problem seems to be something in the hardware. God, I miss lights and switches.... =+=+=+=+=+= Fm: Wilson Van Alst To: Christopher Zach Unfortunately the symptoms you describe could be the result of several ailments. Can you get into BASIC? Try turning the computer on -- and before anything else, press . Then type "BEEP" (without the quotes) and press again. If you hear a BEEP, it would seem to indicate the computer's system software is doing OK and the problem is probably in the LCD and/or its driving circuits. No beep? Things are screwed up at a more fundamental level. If you have a decent volt-ohm meter, you might try a "gross" diagnostic on the power supply. With the computer on, you should be able to measure a steady, accurate 5 volts between pins 7 (gnd) and 9 (+) at the Bar Code Reader socket: 1 2 3 4 5 6 7 8 9 If this measurement is not very close to 5v, or if it fluctuates, the computer's power supply circuitry would be suspect. Incidentally, if you haven't done so already, you should strip the computer to its barest essentials before trying the above: take out any option ROM or RAM chips that are not soldered in place. And while you have the computer case open, take a close look for signs of cracking on the main printed circuit board, give the plugs on those ribbon connectors a healthy back-and-forth wiggle (or even pull them free and re-seat them), and use a hair-dryer, set on cold, to blow away any accumulated dust and debris. Let us know what you learn! =+=+=+=+=+= Fm: Bill Brandon [DPTRAIN] To: Christopher Zach By any chance, do you have an option ROM of some variety installed? If so, check to make sure it's still seated correctly. If you aren't afraid to open up the case of your machine (and I can't imagine a man who will go on line, publicly, on a Silent 700, being afraid of *any*thing), you might check to be sure your add-on RAM chips are secure, too. I have the tech manual for the 100, but you didn't give me enough to use the rinky-tink trouble-shooting chart in the book. Well, maybe not ... The book sez that IF the machine works at all, AND IF the LCD functions at all, THEN the next thing to check is the keys. The chart asks "Keys don't function?". That sounds to me like it's worth checking out: 1) Check if keyboard connector is correctly connected; 2) Check the key scan signal (Is scan signal present at M25 PA0 - PA7 and PB1? IF NOT, check if pulses are emitted from the TP terminal (pin 10) of M18 and M25 at 4 msec intervals.); 3) Check diodes on keyboard; 4) Check the return signal; 5) Check M15, M13, M16, and pull-up resistor MR4; 6) Check the key switching no-input keys. There is also a common step on many of the charts: Check the RESET signal. 1) Check the RESET circuit (Check T11, T10, T9, T25, D20, D22, and C78); 2) Check all ICs which have RESET and RESETbar signals (Check M19, M25, M22, M14, M27, M36, and M31, and also check LCD unit and RAM). =+=+=+=+=+= Fm: Christopher Zach To: Bill Brandon [DPTRAIN] I will give that a try. Being the kind of person who gleefully takes everything apart (and is able to put it together), I have no prob with hauling the cover off. I don't have any option roms, have checked the memory, and (once) ran the machine without the kbd. Didn't change a thing. I will try to check the reset line, maybe that might be the problem... =+=+=+=+=+= Fm: Bill Brandon [DPTRAIN] To: Christopher Zach OK - I reckon that means you have also checked all those little ribbon connectors and found them tight. The next item on the checklist (after one which has you check the buzzer) is "Clock doesn't function": 1) Check the power supply voltage - when power ON: +5V - when power OFF: 2.0-4.0V (if not normal, check power supply circuit) (Note: I think you have been given the Q&D way to do this at the BCR port, so I won't repeat) 2) Check oscillation frequency (f=32.768 kHz) (If not normal, check X1, C17, C18 and M18) 3) Check that a 250-Hz pulse is output from TP signal 4) Check clock-setting IC's (M14 and M25) and RESET signal. The next item on the checklist is "Reset doesn't function", which I sent to you in the previous message. After that the checklist gets into things which don't seem at all related to your problem. =+=+=+=+=+= Starting message #: 188763 Starting date: 15-Oct-89 06:28:33 Participants: Christopher Zach 72735,1140 Gene Nestro 73727,1015 Tony Anderson 76703,4062 Bill Brandon [DPTRAIN] 76701,256 Wilson Van Alst 76576,2735 Stan Wong 70346,1267