justacruzr2 Posted May 3, 2023 Share Posted May 3, 2023 Still trying to figure out which is the problem, drives or cards. I have tried both drives with both the first release CC9900 controller and the REV A controller. The results were the same with both. Neither would "seek". I did connect a different drive awhile back that I bought off eBay and it did work. But now that drive doesn't work either. Anyway, that's why I think the problem is with the drives. But it did make me wonder if there's something wrong with the cards that's killing the drives although I don't know how that could happen. Maybe it's just a coincidence. Let's assume for this discussion that the drives are OK and it's the controllers. When I turn on the PEB, the drives spin up and the LEDs come on until I turn the console on. That's normal. When I turn the console on, the CC9900 screen is displayed, and the drives shut down after a moment. That's normal. When I press 1 for Disk Manager, the drives come on and attempt to load it but beeps after it checks drive 1 and 2 and can't find it. That's normal. When I press 2 for TI Basic it goes right into TI Basic. That's normal. When I press 3 for TI Extended Basic the drives come on and XB attempts to find and run a program on disk1 named LOAD but can't find one so the drive shuts down and returns to the TI Extended Basic ">" prompt. That's normal. When I press space bar for color bar I get the color bar. And if I press the space bar again I get the regular TI menu with "Press 1 for TI Basic" and "Press 2 for TI Extended Basic". That's normal. So with all that appearing normal, could there still be something wrong with those cards? Both of these cards were rebuilt. I replaced everything including the IC's with the exception of the PALs since they're not available. Would the cards still appear to work even if the PALs were bad? Like maybe one of the pins equations is messed up? I know the CC9900 screen is running out of the ROMs. It was my assumption that if the cards work as described above, then the PALs are probably OK. But maybe not? Anyone know for sure? 1 Quote Link to comment Share on other sites More sharing options...
Fritz442 Posted May 3, 2023 Share Posted May 3, 2023 Did you ever connect a 3.5 drive to your CC cards? These floppy drives are usually much more stable to test the card with. 1 Quote Link to comment Share on other sites More sharing options...
RickyDean Posted May 4, 2023 Share Posted May 4, 2023 Might also use a Gotek drive, to see if the controllers are reading and writing. 1 Quote Link to comment Share on other sites More sharing options...
+9640News Posted May 4, 2023 Share Posted May 4, 2023 I went through a bunch of 5.25" drives late last year to discover I had several drives with problems with my CC controller on the Geneve. For awhile, I thought it was maybe related to hardware or cabling. Finally realized it was just bad drives. 1 1 Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 4, 2023 Author Share Posted May 4, 2023 19 hours ago, Fritz442 said: Did you ever connect a 3.5 drive to your CC cards? These floppy drives are usually much more stable to test the card with. No. The only 3.5 drive I have is in my Windows PC. I think these aren't compatible with the CC9900. Am I wrong? I also found some tech info that said the most common problem with floppy drives is the photo optic sensor that reads the index hole. I am ordering a logic probe to see if that's the case. But I would like to eliminate the CC9900 as the problem. Would you say that given the above description of the CC9900 behavior, the controllers are OK? Quote Link to comment Share on other sites More sharing options...
Stuart Posted May 4, 2023 Share Posted May 4, 2023 18 minutes ago, justacruzr2 said: I also found some tech info that said the most common problem with floppy drives is the photo optic sensor that reads the index hole. I am ordering a logic probe to see if that's the case. But I would like to eliminate the CC9900 as the problem. Would you say that given the above description of the CC9900 behavior, the controllers are OK? The controller board is displaying the correct screen and is attempting to access the drives so it sounds mostly OK. You need to be checking the signals from the floppy coming back to the controller board, and back through the interface chips on the controller board. A logic probe will help you do that. Let us know when it arrives. Quote Link to comment Share on other sites More sharing options...
+9640News Posted May 4, 2023 Share Posted May 4, 2023 17 minutes ago, justacruzr2 said: Would you say that given the above description of the CC9900 behavior, the controllers are OK? Likely, the controllers are good. 17 minutes ago, justacruzr2 said: No. The only 3.5 drive I have is in my Windows PC. I think these aren't compatible with the CC9900. Generally, with the CorComp controller card and a 4A, you are going to have issues. You would need at most a 720K 3.5" drive, and 720K 3.5" disks rather than 1.44 MB disks. I do not recall if the CorComp has dips for 40 or 80 track drives or not. I know the Myarc HFDC does, but do not recall the specifics with the CorComp card. Quote Link to comment Share on other sites More sharing options...
Fritz442 Posted May 4, 2023 Share Posted May 4, 2023 (edited) 3 hours ago, justacruzr2 said: No. The only 3.5 drive I have is in my Windows PC. I think these aren't compatible with the CC9900. Am I wrong? Yes, that is wrong, almost ANY 3.5 drive will work on the TI, I have two 3.5's in both my PEB's and use nothing but 1.44 disks all the time. If you know your PC drive is good, just attach it to the TI with the same PC cable (just make sure to only use the straight section..NO FLIPS) this will be DSK2, then cover(on both sides) the right side hole in the 1.44 disk...not the one with the slide lock. Then test the CC controller. Edited May 4, 2023 by Fritz442 1 Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 4, 2023 Author Share Posted May 4, 2023 3 hours ago, Stuart said: The controller board is displaying the correct screen and is attempting to access the drives so it sounds mostly OK. You need to be checking the signals from the floppy coming back to the controller board, and back through the interface chips on the controller board. A logic probe will help you do that. Let us know when it arrives. Thanks Stuart. It won't be here till next week but I'll let you know when I have it. 1 Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 4, 2023 Author Share Posted May 4, 2023 OK. but I still think there will be a problem. The CC Disk Manager is on a 5.25 floppy and the 5.25 floppy drives are the ones that aren't working. I have no way to transfer the program from 5.25 to 3.5. Don't know what good putting a blank 3.5 floppy in the 3.5 drive will do. With nothing on the disk the drive still isn't going to "seek". Is this wrong too? Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted May 4, 2023 Share Posted May 4, 2023 Maybe this will help. TI-99-4A-FLOPPY-DRIVES-TI-99-v1.15-ALL.pdf 2 Quote Link to comment Share on other sites More sharing options...
Fritz442 Posted May 5, 2023 Share Posted May 5, 2023 1 hour ago, justacruzr2 said: OK. but I still think there will be a problem. The CC Disk Manager is on a 5.25 floppy and the 5.25 floppy drives are the ones that aren't working. I have no way to transfer the program from 5.25 to 3.5. Don't know what good putting a blank 3.5 floppy in the 3.5 drive will do. With nothing on the disk the drive still isn't going to "seek". Is this wrong too? I thought you may have had a Disk Manager cart to format and test the disk, as you don't need a CC manager for this. 1 Quote Link to comment Share on other sites More sharing options...
RickyDean Posted May 5, 2023 Share Posted May 5, 2023 Do you have a final grom99, if so you can download DM to it and use it. 1 Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 5, 2023 Author Share Posted May 5, 2023 (edited) 18 hours ago, Fritz442 said: I thought you may have had a Disk Manager cart to format and test the disk, as you don't need a CC manager for this. I sorta guessed that's what you thought. I did originally have the TI disk controller and Disk Manager 2 with 3 of the old Shugart 90K full height drives but when CorComp came out with their controller card I sold the original disk system setup in Micropendium. I suppose I could try eBay and see if someone has a Disk Manager 2 cart for sale. Edited May 5, 2023 by justacruzr2 more info Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 5, 2023 Author Share Posted May 5, 2023 19 hours ago, atrax27407 said: Maybe this will help. TI-99-4A-FLOPPY-DRIVES-TI-99-v1.15-ALL.pdf 29.84 kB · 6 downloads Yes. I found that a few days ago when searching for additional info. I was specifically looking at the TEAC FD55F drive compatibility since there is someone selling them. But they need a mod to double step. The link someone here provided unfortunately is broken so I'm hoping I can find a good link that will show how to do the mod. This is a fallback option right now. I'd like to get the Fujitsu's working again if possible. Also, sometimes a disk made in one floppy drive cannot be read in another from a different manufacturer. I've run into this same problem with CD's on my PC occasionally which is why it's a bit better to read it in the drive that created it. Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 5, 2023 Author Share Posted May 5, 2023 17 hours ago, RickyDean said: Do you have a final grom99, if so you can download DM to it and use it. No. I'll download it but how do I get it into the console for execution. I have a Gramulator but would still need to move it from disk to get it into the Gramulator. Unless you know another way that doesn't require a disk drive? Quote Link to comment Share on other sites More sharing options...
RickyDean Posted May 6, 2023 Share Posted May 6, 2023 There is the Tipi, if you get one of those you make your pc, your drive. Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted May 6, 2023 Share Posted May 6, 2023 Have you checked continuity of your drive cables? Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 8, 2023 Author Share Posted May 8, 2023 On 5/6/2023 at 4:51 PM, atrax27407 said: Have you checked continuity of your drive cables? Yep. All good on all 34 lines. 1 Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 11, 2023 Author Share Posted May 11, 2023 The logic probe arrived yesterday. Here are pictures showing the index hole sensors. They are circled in red. 2 are on the motor pcb and 2 are topside. The 2 that are topside are 3 legged and the 2 on the motor pcb are 2 legged. The one topside one is located in the black "L" shaped housing and is just barely visible thru the slit. All 4 are diodes. Obviously 2 are emitters and 2 are receivers. The ones that are on the motor pcb almost look like the super diodes you see in flashlights. They are a small yellow square. I'm assuming these are the emitters and the topside ones are receivers. Any comments appreciated since I'm not sure how to test these with the logic probe. Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 11, 2023 Author Share Posted May 11, 2023 Also remembered that the Gramulator has a built in cataloging routine so loading a disk manager is not necessary for diagnosing. 1 Quote Link to comment Share on other sites More sharing options...
Duewester Posted May 11, 2023 Share Posted May 11, 2023 Hmm, be nice if you have the prints or a function diagram. Have you watched Adrians digital basement. He does some drive trouble shooting that might give you a heads up. I don't know if you NEED a logic probe to test the LEDs. A multimeter will tell you if they are changing state. You just need to know if they are even being asked to work. Quote Link to comment Share on other sites More sharing options...
Stuart Posted May 11, 2023 Share Posted May 11, 2023 2 hours ago, justacruzr2 said: The logic probe arrived yesterday. Here are pictures showing the index hole sensors. They are circled in red. 2 are on the motor pcb and 2 are topside. The 2 that are topside are 3 legged and the 2 on the motor pcb are 2 legged. The one topside one is located in the black "L" shaped housing and is just barely visible thru the slit. All 4 are diodes. Obviously 2 are emitters and 2 are receivers. The ones that are on the motor pcb almost look like the super diodes you see in flashlights. They are a small yellow square. I'm assuming these are the emitters and the topside ones are receivers. Any comments appreciated since I'm not sure how to test these with the logic probe. So you've got the logic probe. Presumably it has an LED to show logic low, one for logic high, and one to show a pulsing signal, or a similar arrangement? Assuming you have the drive out of the PEB so you can get to the ribbon edge connector easily, I would suggest: (1) Make sure you're clear where pin 1 is on the edge connector, and how the pins are numbered. Google "34 pin floppy drive pinout" if unsure. (2) Manually push the head to mid-position like you've done before, then put the probe on pin 20 and make sure that you get a pulsing signal as the head steps to track 0. We know this is working so is a good test that you're using the probe correctly. (3) Manually push head to mid-position again then put probe on pin 26. This should be steady logic high, and go to a steady logic low when the head reaches track 0. (4) Now the index signal. Put probe on pin 8 and check that you get a pulsing signal while the drive is being accessed and the disk is rotating. (5) Probe on pin 30 which is read data, and see if there is any evidence of a data signal while the drive is being accessed. Stuart 3 Quote Link to comment Share on other sites More sharing options...
justacruzr2 Posted May 15, 2023 Author Share Posted May 15, 2023 On 5/11/2023 at 6:06 PM, Stuart said: So you've got the logic probe. Presumably it has an LED to show logic low, one for logic high, and one to show a pulsing signal, or a similar arrangement? Assuming you have the drive out of the PEB so you can get to the ribbon edge connector easily, I would suggest: (1) Make sure you're clear where pin 1 is on the edge connector, and how the pins are numbered. Google "34 pin floppy drive pinout" if unsure. (2) Manually push the head to mid-position like you've done before, then put the probe on pin 20 and make sure that you get a pulsing signal as the head steps to track 0. We know this is working so is a good test that you're using the probe correctly. (3) Manually push head to mid-position again then put probe on pin 26. This should be steady logic high, and go to a steady logic low when the head reaches track 0. (4) Now the index signal. Put probe on pin 8 and check that you get a pulsing signal while the drive is being accessed and the disk is rotating. (5) Probe on pin 30 which is read data, and see if there is any evidence of a data signal while the drive is being accessed. Stuart It's an Elenco 560. Has all the doodads. Does all types of logic circuits (TTL, CMOS, etc). Thought I should get a decent one and not a cheap one. BTW this is the 1st release controller card I'm testing which uses the WD2793 chip. Also, according to the WD2793 datasheet, the write protect state is not checked unless a write is performed. Anyway, here are the results: ============================================================== WD2793 Controller Test Pin Function Signal Type Test Result === ======== =========== =========== 15 Step Output LO & pulsing 16 Direction Output LO - never changed 34 Track 00 Input HI - never changed 35 Index Pulse Input Rapidly changing from HI to LO & Pulsing * Direction should be HI stepping in & LO stepping out ============================================================== Floppy Drive Test Pin Function Signal Type Test Result === ======== =========== =========== 8 Index Pulse Output Rapidly changing from HI to LO & Pulsing 18 Direction Input HI - never changed 20 Step Input HI & pulsing 26 Track 00 Output HI - never changed ============================================================== Testing of the WD2793 Controller was done by touching the pin. Testing of the Floppy Drive was done by touching the edge connector. The Step, Direction and Track 00 tests were done by moving the Read/Write head to the center(hub). From the test results, the index hole sensors appear to be working properly. What is interesting is the Step and Direction test results. They are opposite of each other. I checked that several times to be sure. And the Track 00 results should have been LO until the head reached the outer edge and then gone HI as you said. So there seems to be a problem with the Track 00 reading which I presume would affect Step and Direction. It's like the keyboard at startup. Setting it to a known state. If where the head position is is unknown then maybe the Step and Direction functions can't be performed. What do you think? Quote Link to comment Share on other sites More sharing options...
Stuart Posted May 15, 2023 Share Posted May 15, 2023 (edited) Step and Direction look OK. They will read opposite on the WD chip pins and on the floppy connector as there are inverters on the output of the FDC card. Does Step keeps pulsing even when the head has visibly reached track 00? See if you can work out how track 00 is detected - often by the head carriage operating a microswitch or breaking an LED sensor beam. Also see if you can follow the track 00 output on the edge connector back to a logic chip on the floppy drive circuit board - the 'mechanism' may be fine but a faulty logic chip on the floppy output. Track 00 is active low - so should be high until it reaches track 00 then go low. Have you got more than one drive you can test? Edited May 15, 2023 by Stuart Quote Link to comment Share on other sites More sharing options...
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