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------------ ************ Topic 15 Mon Jan 19, 1987 R.DEWEESE at 19:47 PST Sub: 1541 Loading Troubles HELP!! WHERE DO I FIND HELP INFO FOR THE 1541 DRIVE. HAVING PROBLEMS, PROBLEMS, PROBLEMS.*S 18 message(s) total. ************ ------------ Category 17, Topic 15 Message 1 Mon Jan 19, 1987 TIGLON.G [*SysOp*] at 22:51 EST R.DEWEESE: What kind of problems are you having with the 1541? Many of us are here to help you! Just let us have some hints as to what is going wrong! -<* Gayle, *FlagShip* SysOp ------------ Category 17, Topic 15 Message 3 Mon Jan 19, 1987 R.DEWEESE at 20:11 PST I AM AN ST OWNER, BUT MY BROTHER HAS THE 64. HES HAVING PROBLEMS WITH HIS 1541 DRIVE, AND I TOLD HIM I WOULD CHECK YOU GUYS OUT AND SEE IF SOMEONE COULD HELP. THE PROBLEM IS AS FOLLOWS: HE ROUTINELY GOES TO "LOAD" A PROGRAM (THE PROBLEM IS NOT UNIQUE TO ANY SPECIFIC PROGRAM.) HE GETS BACK THE "FILE NOT FOUND" MESSAGE, ALTHOUGH THE FILE IS DEFINITELY ON THE DISK, AND MAY HAVE BEEN LOADED JUST PRIOR. ONCE THIS OCCURS, NOTHING SEEMS TO "CLEAR" THE BUG. I.E., HES TRIED REBOOTING, TURNING THE MACHINE OFF AND BACK ON REPEATEDLY, AND ETC. THE ONLY THING THAT WORKS IS INSERTING A NEW DISK AND FORMATTING THE DISK. AT THIS POINT HE CAN TAKE OUT THIS DISK, PUT IN THE DISK HES TRYING TO LOAD, AND IT WORKS FINE, AT LEAST UNTIL THE NEXT TIME IT HAPPENS (SOMETIMES AND HOUR LATER, SOMETIMES 3 DAYS LATER. THERE DOESN'T SEEM TO BE ANY RHYME OR REASON TO IT. HE HAS HAD IT IN TO THE DEALER UMPTEEN TIMES, AND THEY DON'T KNOW WHAT IT IS. HE ALSO HAS A PROGRAM THAT CHECKS OUT THE DISK ALIGNMENT, WHICH HE SAYS IS RIGHT ON. CAN ANYONE HELP?? BEING AN ST OWNER, I DON'T KNOW MUCH ABOUT THE 64'S, BUT CAN ASK MY BROTHER MORE QUESTIONS IF YOU HAVE ANY THOUGHTS. ONCE AGAIN, ANY HELP IS G R E A T L Y !!! APPRECIATED. THANKS, BOB ------------ Category 17, Topic 15 Message 4 Mon Jan 19, 1987 GBARRETT [VISION100] at 22:28 CST The problem with most of the disk alignment programs is that they only check the head alignment relative to its OWN positioning...i.e., they only really check to see if it is in alignment with itself. A truly qualified CBM warranty station would be able to check head positioning, alignment and speed for your on an oscilloscope and come up with some answers...you might try another servicer. -GaryB ------------ Category 17, Topic 15 Message 5 Mon Jan 19, 1987 CHARRINGTON [Courtney] at 21:24 PST I know this sounds doppy...but try move the disj drive further away from the monitor. If it's next to the monitor....you could be having RF problems. It's a far more common problem then most people think. Courtney ------------ Category 17, Topic 15 Message 6 Tue Jan 20, 1987 MICHAEL.M [-:SysOp:-] at 00:45 EST If it is the same program or programs giving him the problems, he might try initializing the drive before loading another file. Do this by typing: OPEN1,8,15,"I":CLOSE1 ------------ Category 17, Topic 15 Message 7 Tue Jan 20, 1987 KEVIN-S. [KeS] at 00:10 PST If the problem is with drive alignment, he might also notice that files CREATED by his drive, such as WP text files, etc., load fine, but there are problems with program and other software written on "good" drives. One more thing to check on. KeS ------------ Category 17, Topic 15 Message 8 Tue Jan 20, 1987 M.FRYER [Ludedude] at 22:42 CST R.DEWEESE I worked for Commodore for about 3 years in the service department. One of the biggest problems was protected software that jacks the head out to track 40 or beyond (although thats supposed to be impossible) and leaves it there. If that is the case with your brother I would agree with Micheal.M about initializing the drive per the instructions he gives in the earlier message. The 'fine' protection that many companys insist on using plays havoc with the 1541, ramming the head places it was not suppose to be anyway. I still believe it should be able to take it though, but as I and many other 1541 users know that is not always the case. Anyway, The drive could still be out of alignment and the trips to the corner repair shop do know good because they are probably not using a 'real' alignment disk and scope to set it up. The problem starts with a 'real' alignment disk costing about $80 or more and a good scope coming in at around $5000 and up. Most repair shops cant handle that kind of expense so they buy the 'superduper' do it yourself kit for $40 and go from there. One last thought, while I was employed by the big C, I saw several problems similar to yours, The cause::: Well......... HUMMMM....... The factory techs say 'no way is there a bug int the software'. I dont think there is either, but, When the drive ROM was replaced the unit NEVER, to my knowledge, and I would have been the first to know, screwed up again. BAD ROM you say.. maybe.. maybe not.. Good luck.. ------------ Category 17, Topic 15 Message 9 Tue Jan 20, 1987 R.DEWEESE at 20:43 PST Thanks you guys for all the help!! I just got off the phone with my brother, and here's the latest: Using a disk speed program, he determined that the drive was spinning at around 300.85 rpm on the average. Using a "do it yourself" manual, he decided to dig into the drive and make an adjustment. He adjusted the speed until he came up with an average speed of appx. 300.02 rpm. Says the drive now works like its never worked before. Oh, he also cleaned the head(s?). You know how that goes; today its fixed and tomorrow its broken. But anyway, so far so good. He said the thing would never load 1st thing in the morning (sleepy, I guess), and this morn ing, no problem. What do you experts think?? Can that seemingly little difference in disk speed make that much of a difference in the performance, or is it likely a result of the cleaning, or a combination of both. We're keeping our fingers crossed that it keeps working!! Anyway, appre te your help, and hope this helps anyone else who might be having the same kind of problem. Better get back to the "ST" board so I can justify this expenditure. Thanks again. Bob ------------ Category 17, Topic 15 Message 10 Tue Jan 20, 1987 CHARRINGTON [Courtney] at 21:36 PST Wouldn't load in the morning ? ** Of course that makes sense! ** It takes me forever to get up to speed in the morning. Why should the drive be different? Courtney ------------ Category 17, Topic 15 Message 11 Wed Jan 21, 1987 DEB [*SysOp*] at 05:29 EST I have an old (white case, even) 1541 which will NOT work in the mornings anymore....it HAS to be warm to run. Me, *I* never pretended to work in any hours which have an 'A.M.' in them!!! How could I blame my disk?? Whatever the cause, it was obviously contagious. ------------ Category 17, Topic 15 Message 12 Thu Apr 23, 1987 THEDOCTOR [STEVE] at 20:39 EDT HELP!!! I don't use a 64 normally but have run in to a need to do so. My problem is that it only has one 1541 and I need to duplicate a disk. Well that should be easy but I sure haven't figured it out! I loaded and ran the program "Single disk backup V1.0" well this give me a nice menu it formats the destination disk then reads in some of the source disk, were moving along fine till it says to put in the destination disk. When i I do that it doesn't like it, it says do it again and again and again> I can't get anywhere what is the simple thing I'm doing wrong?!? Steve (puzzled) ------------ Category 17, Topic 15 Message 13 Thu Apr 23, 1987 CHARRINGTON [Courtney] at 18:42 PDT What does it do when you put the destination disk back in the drive? Are you sure you A) have formatted the disk correctly? B) don't have a write protect tab on the disk? C) it is 'seated' in the drive correctly? Hope some of these work... Courtney ------------ Category 17, Topic 15 Message 15 Sat Apr 25, 1987 THEDOCTOR [STEVE] at 14:02 EDT I've done the following in answer to your suggestions, 1. It must be formated, I can save a program on it. 2. The write protect couldn't be on because of #1. 3. I seems to be seated, I've put it in and out several times always the same response. Steve (still puzzled!) ------------ Category 17, Topic 15 Message 16 Sat Apr 25, 1987 DEB [*SysOp*] at 18:19 EDT me....I'd switch to another piece of software...! ------------ Category 17, Topic 15 Message 17 Sat Apr 25, 1987 TIGLON.G [*SysOp*] at 23:55 EDT Where did you get this Single Disk Backup V1.0 Steve?? Just curious! It sounds like a program out of Fast Hackem'! -<* Gayle ------------ Category 17, Topic 15 Message 18 Sun May 10, 1987 THEDOCTOR [STEVE] at 18:13 EDT I got the software from another office. If I rem ember right it's on a copy of the TEST/DEMO disk? Still stranded ------------ ************ Topic 17 Wed Jan 28, 1987 P.WEST at 01:49 PST Sub: 1541 device numbers Having problems with disk hardware?!! 15 message(s) total. ************ ------------ Category 17, Topic 17 Message 1 Wed Jan 28, 1987 P.WEST at 01:58 PST I recently purchased a second disk drive (a 1571) but have not been succesful changing the 1541 number via hardware. I cut jumper 1 as directed by the manual but the disk still responds as unit 8. Does anyone have any ideas as to what I might be doing wrong. Thejumper was clearly labeled as J1. ------------ Category 17, Topic 17 Message 2 Wed Jan 28, 1987 TIGLON.G [*SysOp*] at 05:31 EST Okie P.WEST: When I cut mine, I cut #1 of the half moon like connections, but I had to do it more than 3 times, just to make SURE the break was there! Try going over it again with your knife (or whatever) and make SURE the break is there! -<* Gayle, *FlagShip* SysOp ------------ Category 17, Topic 17 Message 3 Wed Jan 28, 1987 DEB [*SysOp*] at 06:14 EST I have YET to see a 1541 PCB labled clearly 'J1' !!! SOME of them were labeled 1 and 2, but never one J1 and J2! Methinks that perhaps you may have cut the wrong things! Which 1541 PCB are you working on??! *deb!* ------------ Category 17, Topic 17 Message 4 Wed Jan 28, 1987 S.LEWIS at 21:11 MST Hehehe probably cut the jumper that turns the 41 into a 1001. April Fools... oh... only January. ------------ Category 17, Topic 17 Message 5 Thu Jan 29, 1987 SPARROW.J at 07:41 EST Wait a second..didn't you say you bought a 1571? The 1571 has device switches for this purpose. ------------ Category 17, Topic 17 Message 6 Thu Jan 29, 1987 P.WEST at 04:42 PST My first clue should have been that the jumper was clearly marked! CBM just doesnt do that. The jumper is clearly cut if fact if i go any deaper i may get to the other side. If its any help the pcb no is 251777 and the board is marked REV A. The jumper i cut is near the rear of the board in the center. ------------ Category 17, Topic 17 Message 7 Thu Jan 29, 1987 TIGLON.G [*SysOp*] at 20:04 EST (no Sparrow, he wanted to cut his 1541 and make IT the #9) ------------ Category 17, Topic 17 Message 8 Thu Jan 29, 1987 S.LEWIS at 23:16 MST Near the REAR of the board? Hmmmmm. Left side (facing the slot to insert a disk) I'd buy... Toward the front I'd buy... But the REAR? I think you cut the WRONG DONUT! Makes me wonder what you did accomplish... Steve ------------ Category 17, Topic 17 Message 9 Fri Jan 30, 1987 P.WEST at 02:36 PST Deb gave me the clue! After I logged off I took a microscope to the PC board and found a trace marked "1" instead of "J1" I cut that trace and resoldered the other one and wa-la it worked. leave it to commodore to give two jumpersthe same number! Thanks for all the assistan folks!!!!! - PJW ------------ Category 17, Topic 17 Message 10 Fri Jan 30, 1987 TIGLON.G [*SysOp*] at 06:45 EST Great PJ!!!!!!!! ::Another case SOLVED!:: ------------ Category 17, Topic 17 Message 11 Sat Feb 20, 1988 MARTY.A at 00:12 EST Does anyone happen to know, with the 1541's... revision A, short board...there is a J1, J2, and a J3 jumper, what the J3 jumper does???? ...Marty... ------------ Category 17, Topic 17 Message 12 Sat Feb 20, 1988 DEB [*SysOp*] at 14:17 EST Well, Marty, the J3 shouldn't be together like the J1 and J2, right?! (beats me what it does, tho) Want to cut it and find out?! ::wicked grin:: ------------ Category 17, Topic 17 Message 13 Sat Feb 20, 1988 MARTY.A at 20:15 EST Heh, no, I didn't wanna cut it and find out :-) And yes, it looks just like the J1 and J2... and its together too... Perhaps it controls the device numbers above 11?? ...Marty... ------------ Category 17, Topic 17 Message 14 Sat Feb 20, 1988 WC.COLEMAN [Geos*Sysop] at 23:50 EST You can't set device numbers greater then 11 through the hardware. When the drive is first turned on (or reset) the DOS will check the value of two pins of data port B of VIA 1 ($1800 bits 5 and 6). Since there are two pins that let's you select up to four different device numbers. As far as the jumpers go there are actually at least seven! All of the others are just there to allow different component selections on the same board (the boards go thru minor component changes from time to time, add a resistor, remove a cap, etc.). ------------ Category 17, Topic 17 Message 15 Sun Feb 21, 1988 DEB [*SysOp*] at 15:56 EST In Older CBM drives, there were indeed three jumpers, all for device numbers. Maybe they started doing it AGAIN?! Lord knows they've moved around the device number traces enough and messed with enough different PCB's to have changed anything...! ** ------------ ************ Topic 27 Tue Jun 30, 1987 D.AIR at 21:52 MDT Sub: Screwy 1541 disk drives MY 1541 seems to've decided that it doesn't like commercial software anymore. When trying to access the first track, it clatters and refuses to load. I've tried to realign it, but no good. HELP ME!! 22 message(s) total. ************ ------------ Category 17, Topic 27 Message 1 Tue Jun 30, 1987 D.AIR at 22:02 MDT To continue... It seems that the head wont go all the way to the edge of the disk. I followed the guide for aligning the head from RUN #19 (July 1985), and the little reader program said everything on track 1 was zoot. But the Test/Demo disk's performance test said there was a #20 READ ERROR for track #1 when reading and writing to there. I moved the motor all over, but that only made the red light blink and the ERROR message changed to a #27. I don't know what else to do, save for an expensive service call or sending the damn thing back to commodore for replacement. ...Any answers? ------------ Category 17, Topic 27 Message 2 Wed Jul 01, 1987 DEB [*SysOp*] at 14:12 EDT There are usually people in your local user group who can realign your 1541 with the proper equipment. Here in Fresno, this costs $25 only! Beats paying for a new drive! You need someone to use a scope on it...I don't think it sounds like you will require anything else but a good realignment! *deb!* ------------ Category 17, Topic 27 Message 3 Wed Jul 01, 1987 MICHAEL.M [-:SysOp:-] at 19:24 EDT Before you send out for repairs, try shoving that little cardboard disk (which came with the 1541) back in the drive. Then re-try to load a few programs. Only takes a second, and may not work, but it cant hurt! (Lord knows it has solved some *very* strange problems for lotsa folks) ------------ Category 17, Topic 27 Message 4 Sat Jul 04, 1987 D.AIR at 16:46 MDT I tried both of the above. I can't seem to find the local UG, and the shops don't service Commodore. As for the cardboard, it fixed it some, but the performance test failed again I think it has something to do with the track 1 stop, as that's the only one that doesn't write or read properly (but ONLY on newly formatted disks; older disks read fine) I'm still perplexed. P.S. I also can't seem to find Commodore. ------------ Category 17, Topic 27 Message 5 Sun Jul 05, 1987 SPARROW.J at 04:07 EDT Commodore North America is headquarted in West Chester, PA, specifically: Commodore Computers 1200 Wilson Drive West Chester PA 19380 215-431-9100 Commodore International has officees in New York, but I don't have the the specific address handy. Let me know if you need any further assistance locating Commodore. --Sparrow James ------------ Category 17, Topic 27 Message 6 Sun Jul 05, 1987 B.HAYFORD at 06:23 EDT D.AIR: I had the same experience with one of my 1541's and it was the stop. All that ratcheting with protected software finally knocked it out of alignment. After sending it out to a local repair shop three times (with no results) I decided to try TRIAD (see ad in Compute Gazette). They returned it to me very quickly and with an alignment job that stuck! Also, since then I had alignment problems with another drive and decided to do it myself - I purchased a disk alignment program (from Cardinal Software I think) and everything went fine! The advantage to this method is that you can make a printout of the alignment graph before anything goes wrong and when it does (I say 'when' because MURPHY is an inhabitant of my house) you can align the drive back the way it was (not necessarily so when done by a commercial repairman) so you will not have difficulty reading your old disks. Hope this helps - Bert Hayford (b.hayford) ------------ Category 17, Topic 27 Message 7 Tue Jul 07, 1987 DEB [*SysOp*] at 20:21 EDT and note that Commodore does NOT repair drives or realign them. They might be happy to charge you for a new one, though. Let me check around for people who do good repair work thru the mail for you. *deb!* ------------ Category 17, Topic 27 Message 8 Sun Aug 16, 1987 R.KUCENSKI [digital doc] at 19:30 PDT For those of you with speed/ alignment problems, I recommend the "Vorpal Utility Kit" from Epyx. It comes with a speed check and an alignment check/ repair program that works very well. I was having trouble getting my old (white case) 1541 to work properly and used this program to check disk speed and head alignment. Turns out head was ok, but speed was hovering around 302 rpm. New drives are set right on 300. Re-adjusting drive speed to 300 +/- 0.10 cleared up all my problems. ------------ Category 17, Topic 27 Message 9 Sun Aug 16, 1987 R.KUCENSKI [digital doc] at 19:51 PDT For those of you who want to adjust disk speed on the 1541, 1. Turn off the power and unplug all cables from back of unit. 2. Turn unit upside down and remove 4 screws from bottom. 3. CAREFULLY turn unit right side up and lift off top plastic cover. 4. Looking at the unit from the front, you will find two screws on the left side which hold a metal cover in place. Remove these and remove the metal cover. 5. Along the left side of the printed circuit board are 5 connectors. Remove the one closest to the rear of the unit. 6. Remove the 6 screws holding the bottom half of the plastic cover and remove the cover. 7. Turn the unit upside down and reconnect the data and power cables. 8. Load a speed checking program such as that contained in the "Vorpal Utility Kit" and run it so you have a continuous speed readout. 9. With the unit upside down and facing towards you, you will find a small circular opening on the front left. 10. Using a jewellers screw- driver, adjust the variable resistor under this hole until drive speed is as close to 300 rpm as possible. (Clockwise is slower, counter-clockwise is faster.) 11. Re-assemble the unit following the steps above in reverse order. ------------ Category 17, Topic 27 Message 10 Sat Dec 24, 1988 D.BRYAN at 13:27 EST I have a drive 1541 problem as well. After setting readjusting the head alignment several times I finlly ally made the big mistake and my drive quit working altogether. The drive will come on, but and when I tra y to access it the computer knows that it is there, but nothing happens. The motor will not run al t all. I took the drive to get it repaired, but the guy said in would cost around $125, which I figure is the same cost to replace the whole inside. Is this drive now uselye ess. Have any ideas?*s ? ------------ Category 17, Topic 27 Message 11 Sat Dec 24, 1988 WC.COLEMAN [GeoOp] at 23:05 EST Did the repair guy say what was wrong? You might open it up and check the obvious first. Make sure the connecter going from the main board to the motor board is connected. In fact make sure everything is connected properly. If that doesn't work the problem is probably on the motor board which I don't think runs $125. -WC ------------ Category 17, Topic 27 Message 12 Sun Dec 25, 1988 C128.CPM [Bill] at 00:44 EST There are many disk drive repair centers that advertise in most C64 mags. Pick one out that is close to you and get a quote. A 1541 is not worth a 125 repair bill, when for a tad more you can get a clone, or a used drive. Bill J. ------------ Category 17, Topic 27 Message 13 Sun Dec 25, 1988 WC.COLEMAN [GeoOp] at 16:56 EST Better yet for under $200 you can get a 1571 or '81 (why anyone would buy a 1541 in this day and age is beyond me). -WC ------------ Category 17, Topic 27 Message 14 Mon Dec 26, 1988 DO.RAE.MI at 19:49 EST Well, there are also a number of commodore repair places that put ads in the computer shopper too. & WC, if a body wants to get to the commercial software, given the unavailability of 1571s in numbers & clone objections to commercial software, it's 1541. sigh. Suggest, you try more than one local repair shop too for estimates. The quality of repair work varies greatly! So does price. Ted ------------ Category 17, Topic 27 Message 15 Mon Dec 26, 1988 DIGITAL.DOC [Digital Doc] at 21:18 PST I agree with Ted. It sounds like the guy you talked to just wants to punish you for opening the drive. Look around more. His price seems too high. <Doc> ------------ ************ Topic 60 Mon Jan 02, 1989 D.THEWS at 22:13 CST Sub: 1541 Disk Troubles 1541 Drive Motor ON constantly 6 message(s) total. ************ ------------ Category 17, Topic 60 Message 1 Mon Jan 02, 1989 D.THEWS at 22:16 CST Can anybody out there help me ?? I recently acquired a very old 1541 disk drive (white case, even) to use with my C64 (there really s is a use for them, especially at Development Test Stations). The problem is that when powered on, the drive motor stays on constantly ( it should stop after a second or so ). Any help on this problem, or where I could acquire a schematic would be greatly appreciated. .......THANX...... DAT ------------ Category 17, Topic 60 Message 2 Tue Jan 03, 1989 C128.CPM [Bill] at 10:19 EST Sounds like the Drive Motor Servo Ckt is bad (guessing here), or the logic controller. Check out Q4 (the larger TO cased TRS that is heat- sinked, and connector P-5 pin 3. P-5 pin 3 is from the controller ckt. There are several books that one must hunt for. One is the '1541 Maintenance Guide' by M. Peltier published by Peltier Ind Inc. 735 N Doris, Wichita, Kansas 67212. CBM might have a book for sale, also. I'd ship it in for repairs, though, and let the 'pro's' do it, as you can damage yourself real easy. Lighting up your life <grin> or your drive really hurts! ------------ Category 17, Topic 60 Message 3 Wed Jan 04, 1989 DO.RAE.MI at 20:45 EST Hmm. Have you tried flicking the drive off & then on after a moment of rest with the c64 on? This works with certain software that hates my 1581. It's worth a try. Failing that, it's repair time. Sigh. Useful for Development whatzit? Could use explain that use? Nosey Ted ------------ Category 17, Topic 60 Message 4 Wed Jan 04, 1989 D.THEWS at 22:30 CST I recently acquired a copy of a 1541 schematic from "Sam's Photo Facts". Unfortunately, the my model is about 3-4 years older than the model shown in the book. There is no heat-sinked transistor at Q4 (and this model uses 4 2114 RAM chips and 2 different ROM chips). The bookstore does have the book you mentioned, and I have ordered it. I would, however, like to fix it myself (it's the challenge that's intruiging). I do suspect the ROM chips, as I think that the power up self test (checksum, etc.) is not passing, leading to the system being in the reset state constantly (from Sam's Photo Fact diagnostics). As for the other question, I am trying to build a Development Test Station. My company builds a lot of specialized systems (software and hardware) for a broad range of clients. I am trying to build a system that can interface with a generic system (one which I use as a base for all systems that I build for prototypes of a clients system). I then build upon this base system (CPU,ROM,RAM,etc.) in order to get the job done (voice recognition, message passing, etc.). When the prototype is built, I will use the development test station to test the circuit (data recording, processor state, I/O port control). This way I can test the single board to ensure in works, before I hook it up with other systems (if you wait until here to test, you never know which system is at fault). Anyway, I got this C64 and disk drive (scrap). I repaired the C64 to working condition, but I'd like the disk drive to save some resident diagnostic software. I guess this is getting kind of windy, so I'll leave it at that. Thanx for the help. Any other comments would be helpful .. DAT .. ------------ Category 17, Topic 60 Message 5 Wed Feb 08, 1989 DIGITAL.DOC [Digital Doc] at 21:51 PST check the transistor that turns the drive motor on and off. Also associated circuitry. <Doc> epair bill, when for a tad more you can get a clone, or a used drive. Bill J. ------------ Category 17, Topic 27