Opry99er Posted March 3, 2019 Share Posted March 3, 2019 Quick rundown: At the CTIUG meeting, we had an issue with a PBox or card or something. We were able to read and write to disks just fine, and we initialized and formatted a couple of disks. On our third initialization attempt, the system refused to format a disk. It still reads and writes just fine, but it will not initialize. We tried multiple 32k cards, multiple disks, and 3 different disk managers. We also swapped drives. We can read previously formatted disks, AND write to them--just cannot format/initialize. What in the good hell would cause this? Consoles tried: Modified console (Vic Steerup) Unmodified console (Ron Klein) 32k tried: 32k onboard a RAMDisk Standard TI 32k Drives tried: Two separate 5.25" TEAC half height double sided drives Disk managers tried; MENU Disk manager (on RAMDisk) DM1000 (on FinalGROM) TI standard Disk Manager 2 cartridge DM1000 (on XB2.7 cart) Floppies tried: 4 different brands, all known to work on other systems. Quote Link to comment Share on other sites More sharing options...
+videofx Posted March 3, 2019 Share Posted March 3, 2019 The only thing that I don't see listed is a different floppy controller. The floppy controller sounds like the culprit. Also just for giggles I would try the floppy controller in a different slot in the PEB Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted March 3, 2019 Share Posted March 3, 2019 Track 0 dead? Quote Link to comment Share on other sites More sharing options...
Opry99er Posted March 3, 2019 Author Share Posted March 3, 2019 I was thinking floppy controller as well... Thinking though, why would it be able to read and write, but not initialize a disk? Weird! We will try moving the disk controller to another slot. That's a good idea. Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted March 3, 2019 Share Posted March 3, 2019 Maybe your controller can't access to track 0, this track is accessed during the format operation. 1 Quote Link to comment Share on other sites More sharing options...
Opry99er Posted March 3, 2019 Author Share Posted March 3, 2019 Interesting... wonder what would cause that, fabrice? I need to look at the schematic I suppose Quote Link to comment Share on other sites More sharing options...
mr_gw454 Posted March 3, 2019 Share Posted March 3, 2019 I just tried moving the controller. That did not seem to help. I am still able to read and write disks without issue, just can't initialize them. Such a strange issue! What part(s) in the controller could fail and still allow most functions to work? Thanks everyone for your help so far. Really appreciate it! Quote Link to comment Share on other sites More sharing options...
HOME AUTOMATION Posted March 3, 2019 Share Posted March 3, 2019 Sometimes drives fail in a manner that causes physical damage to the disks! Particularly the to the inner or outer tracks, this can permutate the results when diagnosing other problems, if unnoticed. Quote Link to comment Share on other sites More sharing options...
+Lee Stewart Posted March 4, 2019 Share Posted March 4, 2019 As long as you use only 90 KiB diskettes in the system, you could try FORMAT-DISK and/or DISK-HEAD with TI Forth to see whether sectors 0 – 3 can be written. See Chapter 5 of the TI Forth Instruction Manual (2nd LES Edition) in the TI-99/4A development resources thread. ...lee Quote Link to comment Share on other sites More sharing options...
+arcadeshopper Posted March 4, 2019 Share Posted March 4, 2019 I've seen specific drives act this way. It is likely a cap gone bad on the drive or controller.. after this many years.. people have complained they cant format the disks i sell on the pushbang drives for instance, but replacing them solves the problem Greg Quote Link to comment Share on other sites More sharing options...
sparkdrummer Posted March 4, 2019 Share Posted March 4, 2019 If you have one of the disks you formatted before things went flakey I would VERIFY that disk to see if all sectors check ok. I then would check that same disk in another system. Possibilitys I thought of were head alignment went south or motor speed if off. Another possibility is see how free the head moves on the rails. Quote Link to comment Share on other sites More sharing options...
RickyDean Posted March 4, 2019 Share Posted March 4, 2019 If this FDC card has socketed IC's, take each one out and test it on a Mini Pro or some similar device to see if there are problems there. You haven't stated a controller brand so at this time I am assuming a TI controller, so unless there has been mods done in the past, I would say that all the IC's are soldered straight to the board, which will make it much harder to diagnose. I just got two Foundation Memory cards functional again last week by testing and finding some bad IC's, due to age and storage. Quote Link to comment Share on other sites More sharing options...
mr_gw454 Posted March 4, 2019 Share Posted March 4, 2019 I appreciate everyone's suggestions so far. As an FYI, this issue is being experienced with 2 identical TEAC drives. I only have a cable that supports the use of a single floppy drive, but swapping drives (for testing) produces the same results. Disks can be read and written to, just not formatted. If I write to a disk in one drive, it can be read back without issue on the other drive. I am looking for one more 5.25" drive to add to the test. Thanks! Quote Link to comment Share on other sites More sharing options...
+FarmerPotato Posted March 4, 2019 Share Posted March 4, 2019 Quick rundown: At the CTIUG meeting, we had an issue with a PBox or card or something. We were able to read and write to disks just fine, and we initialized and formatted a couple of disks. On our third initialization attempt, the system refused to format a disk. It still reads and writes just fine, but it will not initialize. We tried multiple 32k cards, multiple disks, and 3 different disk managers. We also swapped drives. We can read previously formatted disks, AND write to them--just cannot format/initialize. What in the good hell would cause this? I looked for IO Error 43 in the TI disk DSR source code. I did not find it yet. It means Illegal Operation on Seek/Rewind/Restore. Some guesses: 1. I wonder what is the expected error when you enable Protect Disk (the anti-copy protection flag, letter P on sector 0) 2. There was an error trying to move the head to a particular track (but this should be a 6 not a 3) Maybe it is a power supply issue. Try a different Pbox? Drives draw the most power when spinning and seeking. 1 Quote Link to comment Share on other sites More sharing options...
+arcadeshopper Posted March 4, 2019 Share Posted March 4, 2019 are both drives powered up? if so try with just one powered and the other completely unplugged Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted March 4, 2019 Share Posted March 4, 2019 Have you checked the cable for continuity? Quote Link to comment Share on other sites More sharing options...
mr_gw454 Posted March 5, 2019 Share Posted March 5, 2019 are both drives powered up? if so try with just one powered and the other completely unplugged I need to check that tonight after work. Quote Link to comment Share on other sites More sharing options...
mr_gw454 Posted March 5, 2019 Share Posted March 5, 2019 Have you checked the cable for continuity? No I have not. Is there a pin specifically related to the disk initialize process? I needed a dual floppy cable and planned to order a new one from ArcadeShopper soon. Quote Link to comment Share on other sites More sharing options...
mr_gw454 Posted March 5, 2019 Share Posted March 5, 2019 If this FDC card has socketed IC's, take each one out and test it on a Mini Pro or some similar device to see if there are problems there. You haven't stated a controller brand so at this time I am assuming a TI controller, so unless there has been mods done in the past, I would say that all the IC's are soldered straight to the board, which will make it much harder to diagnose. I just got two Foundation Memory cards functional again last week by testing and finding some bad IC's, due to age and storage. Yes, it is a TI controller. I'm looking for any working loaner to see if it helps with the issue. 1 Quote Link to comment Share on other sites More sharing options...
mr_gw454 Posted March 5, 2019 Share Posted March 5, 2019 I looked for IO Error 43 in the TI disk DSR source code. I did not find it yet. It means Illegal Operation on Seek/Rewind/Restore. Some guesses: 1. I wonder what is the expected error when you enable Protect Disk (the anti-copy protection flag, letter P on sector 0) 2. There was an error trying to move the head to a particular track (but this should be a 6 not a 3) Maybe it is a power supply issue. Try a different Pbox? Drives draw the most power when spinning and seeking. Power supply has been mentioned twice. I do have access to an empty (spare) PEB and will be trying that out as well. Quote Link to comment Share on other sites More sharing options...
mr_gw454 Posted March 5, 2019 Share Posted March 5, 2019 As long as you use only 90 KiB diskettes in the system, you could try FORMAT-DISK and/or DISK-HEAD with TI Forth to see whether sectors 0 – 3 can be written. See Chapter 5 of the TI Forth Instruction Manual (2nd LES Edition) in the TI-99/4A development resources thread. ...lee Hi Lee. I'm interested in this test. I've never used Forth, but will look for it and see what happens. Thank you! Quote Link to comment Share on other sites More sharing options...
mr_gw454 Posted March 26, 2019 Share Posted March 26, 2019 Latest updates. Replaced the Disk Controller. Same issue. Can READ/WRITE but not initialize/format. Same behavior for both floppy drives. Tried numerous disk/disk brands. Waiting for new floppy drive cable from Arcade Shopper. Have another 5.25" drive I will try as well. Still hard to believe 2 drives can be bad at the same time, but will continue to troubleshoot. Can anything else in the PEB itself cause this issue? Thanks! Quote Link to comment Share on other sites More sharing options...
RickyDean Posted March 26, 2019 Share Posted March 26, 2019 (edited) Latest updates. Replaced the Disk Controller. Same issue. Can READ/WRITE but not initialize/format. Same behavior for both floppy drives. Tried numerous disk/disk brands. Waiting for new floppy drive cable from Arcade Shopper. Have another 5.25" drive I will try as well. Still hard to believe 2 drives can be bad at the same time, but will continue to troubleshoot. Can anything else in the PEB itself cause this issue? Thanks! Have you checked the drive models to be sure they are not 1.2 mb drives, first thing, google them if you don't know for sure they are 360k drives . Then I would have to say, you may have a logic chip failure in the flex card or a DSR conflict somewhere? Not knowing your set up. Also could be a signal not processing out of the side of the TI itself, but I am not an expert. Edited March 26, 2019 by RickyDean Quote Link to comment Share on other sites More sharing options...
mr_gw454 Posted April 5, 2019 Share Posted April 5, 2019 Hey everyone - latest update. I was able to find another set of drives to borrow/test. Mitsumi D502 (aka TRS-80 Color Computer FD-502). I was able to obtain the correct molex power adapters (as these drives use a much smaller power plug). I was also able to figure out the correct jumper settings to set the drive select properly. I am now able to initialize disks, but these drives have there own set of problems (perhaps need cleaning, etc.). In any case, hard to believe I had 2 drives go bad (in the same way) and can do everything but initialize disks. Such a strange issue. I'm now looking for an inexpensive pair of good drives as I still like to use "old-school" disks on occasion. Thank you for everyone's feedback and help! Quote Link to comment Share on other sites More sharing options...
Opry99er Posted April 5, 2019 Author Share Posted April 5, 2019 Good to see the progress!! Quote Link to comment Share on other sites More sharing options...
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