macnjam Posted April 4, 2016 Share Posted April 4, 2016 (edited) Hi, I have an Apple IIe and a II Plus which were working and now are not booting software. I have been using both and to do that required sharing two Disk II drives between them. I am now afraid I fried something when I swapped the drives. FYI I always had the power off and the power cable disconnected when I moved the drives one one system to another. Perhaps static fried a chip? Symptom on both systems is that when I turn them on to autoboot the Disk II drive makes a normal boot sound, it display the Apple II symbol and the disk spins, but nothing happens. Have tried this with multiple disks. If I do a reset the disk stops spinning. Also, if I manually do a IN#6 it will do the same thing. One weird symptom is if the Disk II card is in any of the slots it will attempt to boot, which i thought was only supposed to happen if the card was in slot #6. I have two Disk II cards and they are doing the same thing. I am baffled. Any help appreciated. Joe Edited April 4, 2016 by macnjam Quote Link to comment Share on other sites More sharing options...
david__schmidt Posted April 4, 2016 Share Posted April 4, 2016 I am now afraid I fried something when I swapped the drives. FYI I always had the power off and the power cable disconnected when I moved the drives one one system to another. Perhaps static fried a chip? It is easy to be off-by-one with the ribbon cable if you have the old, keyless 20-pin header version of the Disk II interface card, which does in fact fry a chip on the analog controller board of the drive. Symptoms are exactly as you describe. Definitely stop inserting disks, as this fried chip makes the drive erase track 0 on any disk it encounters. Can you bootstrap an operating system via audio or serial with ADTPro and do some disk formatting tests? One weird symptom is if the Disk II card is in any of the slots it will attempt to boot, which i thought was only supposed to happen if the card was in slot #6. No, that is expected. The controller can be in any slot; it's just that the typical slot used/recommended is #6. Quote Link to comment Share on other sites More sharing options...
macnjam Posted April 4, 2016 Author Share Posted April 4, 2016 Thanks. I don't have a way to test further and would like to replace the chips. What chip is it and where could I obtain them? Thanks again! Quote Link to comment Share on other sites More sharing options...
Nukey Shay Posted April 4, 2016 Share Posted April 4, 2016 Dumb question...but did you try swabbing the head? Crap tends to build up using this old stuff. And the card should allow the drive to boot regardless of slot number AFAIK. The #6 thing was just good practice (since tons of software was written with this slot in mind). Because when the machine scans for devices, it starts at the last slot #7. Hence, #7 became the "roll yer own card" slot, and the next highest one is #6. Quote Link to comment Share on other sites More sharing options...
macnjam Posted April 4, 2016 Author Share Posted April 4, 2016 I did clean the heads. I think it is the chip because the issue started when I swapped the drives. Anyone know of a source for a 74LS125 IC in Atlanta? I googled this issue more directly and that is the chip that blows if you misalign the ribbon cable. Quote Link to comment Share on other sites More sharing options...
david__schmidt Posted April 4, 2016 Share Posted April 4, 2016 Thanks. I don't have a way to test further and would like to replace the chips. What chip is it and where could I obtain them? http://apple2.org.za/gswv/a2zine/faqs/Csa2FDRIVE.html#012 Electronics houses such as mouser.com and so on will stock it. Quote Link to comment Share on other sites More sharing options...
macnjam Posted April 4, 2016 Author Share Posted April 4, 2016 Update. I was able to obtain the correct chip locally this morning and swapped it in both my Disk II drives. One of the chips showed damage, one did not. Now when i try to boot I am getting the same issue. Perhaps it is because I have a bad disk? Would the sector 0 issue demonstrate the same issue? Disk II drive makes a normal boot sound, it display the Apple II symbol and the disk spins but nothing happens. Thanks again for everybody's help! Quote Link to comment Share on other sites More sharing options...
macnjam Posted April 4, 2016 Author Share Posted April 4, 2016 ok, another update. Using ADTpro (thanks David, was not aware it existed) I got DOS on the //e and now get the message DISK ERROR I/O when I try a CATALOG or INIT HELLO command. I tried this using both the controller cards and both drives. Does this error point at the drive or the interface card? No visible signs of damage (chips or capacitors) on the cards or the drives. I read that this could be the MC3470 chip on the drive? Thoughts anyone? Thanks! Quote Link to comment Share on other sites More sharing options...
david__schmidt Posted April 4, 2016 Share Posted April 4, 2016 (edited) Update. I was able to obtain the correct chip locally this morning and swapped it in both my Disk II drives. One of the chips showed damage, one did not. Now when i try to boot I am getting the same issue. Perhaps it is because I have a bad disk? Would the sector 0 issue demonstrate the same issue? Yes, the blown chip would wipe track 0 and nothing would happen at boot. Do you have any other bootable disks that you didn't run through the suspect drive/chip? ok, another update. Using ADTpro (thanks David, was not aware it existed) I got DOS on the //e and now get the message DISK ERROR I/O when I try a CATALOG or INIT HELLO command. Ok, that's bad. If you have DOS 3.3 loaded and INIT HELLO produces an I/O error, you've still got a physical problem somewhere. You're not using HD media by chance, are you? How about connecting a drive on the second connector and doing INIT HELLO, D2 ? I tried this using both the controller cards and both drives. Does this error point at the drive or the interface card? No visible signs of damage (chips or capacitors) on the cards or the drives. I read that this could be the MC3470 chip on the drive? It could be anything, really... are you absolutely sure the ribbon cable was placed on the header correctly? Edited April 4, 2016 by david__schmidt Quote Link to comment Share on other sites More sharing options...
macnjam Posted April 4, 2016 Author Share Posted April 4, 2016 Hi, yes I am connecting ribbon cables correctly. And the init hello,d2 gave same error. I am guessing it is not the controller so i bought a disk 2 off ebay that is listed as tested and works. Will try that hopefully by end of the week and report back. Thanks again. Quote Link to comment Share on other sites More sharing options...
R.Cade Posted April 4, 2016 Share Posted April 4, 2016 Plugging in the cable wrong can blow all kinds of stuff on the card and the drive, and can then blow other cards and drives you try after that, creating quite a mess. It's usually not just one chip unless you realized your mistake very very quickly and powered everything down. If you tried multiple disks for several minutes, you've got multiple failures... Quote Link to comment Share on other sites More sharing options...
macnjam Posted April 4, 2016 Author Share Posted April 4, 2016 So I could blow the good drive hooking it to one of the suspect controller cards, correct? Lovely! Quote Link to comment Share on other sites More sharing options...
Keatah Posted April 4, 2016 Share Posted April 4, 2016 Sometimes vintage micros have a way with teaching one to be careful with connectors and such things. Better that than a 240V line! Quote Link to comment Share on other sites More sharing options...
macnjam Posted April 5, 2016 Author Share Posted April 5, 2016 I have decided to replace the four chips on the Disk ll controllers. I found the Apple Disk ll tech document and that is what it oulines in the troubleshooting. I will report my results. Quote Link to comment Share on other sites More sharing options...
macnjam Posted April 5, 2016 Author Share Posted April 5, 2016 (edited) So some good news. By replacing the four chips on each Disk II fixed the problem on both the drives. FYI the Apple II controllers were undamaged in this incident. Thanks for everyone's help! It was worth the trouble just to learn that ADTPro existed, and I see that Dave is the author. Wow. Thanks again David! This week I dusted off my Apple II's which have been dormant. The Apple II Plus was my first computer in 1983 and I had moved to the Mac by 1987. It is really fun to get back with my first love! One final question is if there is a way to salvage a few disks that had sector zero overwritten? Thanks, Joe Edited April 5, 2016 by macnjam Quote Link to comment Share on other sites More sharing options...
R.Cade Posted April 5, 2016 Share Posted April 5, 2016 (edited) It's the whole track, not just sector 0. I think everything you need is on that track (RWTS) so it would take some doing to recover anything. Edited April 5, 2016 by R.Cade Quote Link to comment Share on other sites More sharing options...
Keatah Posted April 5, 2016 Share Posted April 5, 2016 Typically on a standard DOS 3.3 disk, Tracks 0, 1, and 2 contain DOS. Track $11 is the VTOC or Catalog. If you've got a disk with damaged track 0, why not just copy that track from a known similar disk. Or simply boot the system with a good DOS 3.3 disk and then insert the "damaged disk. The programs will still be there. OR you could just copy the files from Disk 1 to Disk 2 with FID or Copy II Plus.. Lotsa ways to go about fixing the problem! Quote Link to comment Share on other sites More sharing options...
The Usotsuki Posted April 6, 2016 Share Posted April 6, 2016 (edited) Copy ][+ also has "Copy DOS" which just copies tracks 0-2 from one disk to another. Also, MASTER CREATE on the DOS 3.3 system disks rewrites tracks 0-2. Edited April 6, 2016 by The Usotsuki 1 Quote Link to comment Share on other sites More sharing options...
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