justrob Posted January 2, 2016 Share Posted January 2, 2016 I'm participating in the retrochallenge this round and I'm needing some technical assistance with my 1050 drive. I had a previous post about it here, but I've dived a bit deeper into it this time around. Basically, the thing doesn't read any floppy I've tried in it, and I've tried all 97 floppies I own. The drive seems to have a homebrew US Doubler mod added to it, but I'm not sure how complete or successful it was. I've checked all the usual culprits; device switches set to drive 1, track 0 sensor, all the jumper cabling is plugged in correctly. I took a little vid of what happens when trying to use the drive. I kinda went stupid and filmed it vertically, but it should be clear enough. https://www.youtube.com/watch?v=o6M6rQyz8lM Any help would be greatly appreciated. Quote Link to comment Share on other sites More sharing options...
djmat56 Posted January 2, 2016 Share Posted January 2, 2016 first thing to check......and sorry if this is obvious....is the drive set to drive 1 via the switches on the back? try moving them back and forth a few times then back to drive 1. Also, check that the US Doubler mod is seated correctly. I had a drive with a Happy mod installed which became loose during transit. Removing and reseating solved a similar issue. Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted January 2, 2016 Share Posted January 2, 2016 You are getting NAKs from the 1050 controller. It isn't even trying to read the disk over SIO. Do you see where the drive spins for a few seconds when you insert a disk? That usually indicates that the controller read the disk and is waiting for a command. When your system queries the drive, it doesn't even try to read the disk - it just NAKs. If your 1050 is the only device on the SIO, it is probably bad. Try a new 3086 chip. Bob Quote Link to comment Share on other sites More sharing options...
justrob Posted January 2, 2016 Author Share Posted January 2, 2016 Yep, both switches are to the left, so Drive 1. I gave all of the socketed chips a little push down to make sure they were seated, and got a close look to make sure none had pins sticking out the end or anything. All that was done before I posted though. Wanted to make sure I took care of the most obvious things first. Quote Link to comment Share on other sites More sharing options...
justrob Posted January 2, 2016 Author Share Posted January 2, 2016 (edited) You are getting NAKs from the 1050 controller. It isn't even trying to read the disk over SIO. Do you see where the drive spins for a few seconds when you insert a disk? That usually indicates that the controller read the disk and is waiting for a command. When your system queries the drive, it doesn't even try to read the disk - it just NAKs. If your 1050 is the only device on the SIO, it is probably bad. Try a new 3086 chip. Bob Still new to the Atari stuff. Which one is that? I've attached a shot of the chips. Edited January 2, 2016 by justrob Quote Link to comment Share on other sites More sharing options...
MrMartian Posted January 2, 2016 Share Posted January 2, 2016 Still new to the Atari stuff. Which one is that? I've attached a shot of the chips. Not there, it's one of the discrete chips towards the back of the drive. Quote Link to comment Share on other sites More sharing options...
justrob Posted January 2, 2016 Author Share Posted January 2, 2016 Found the chip. Little bit of googling goes a long way Are these easy enough to source? Looks like a simple desolder and replace job so shouldn't be too bad. Quote Link to comment Share on other sites More sharing options...
Kyle22 Posted January 2, 2016 Share Posted January 2, 2016 Ebay link: http://www.ebay.com/sch/i.html?_nkw=CA3086&clk_rvr_id=960918206727&mfe=search Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted January 2, 2016 Share Posted January 2, 2016 Yes - this one. They are pretty common. (and cheap) Add a socket when you de-solder the chip. Bob 1 Quote Link to comment Share on other sites More sharing options...
justrob Posted January 4, 2016 Author Share Posted January 4, 2016 While I wait for parts to come in, are there any alternatives to this diagnosis? Or is this pretty definitvely the cause of my issues? Quote Link to comment Share on other sites More sharing options...
+bob1200xl Posted January 4, 2016 Share Posted January 4, 2016 Anything that trashes the SIO will cause errors such as yours. Could be broken traces on the SIO connector (try the other connector) or a defective discrete part (unlikely). I'd give the 3086 a 1:3 chance... Bob Quote Link to comment Share on other sites More sharing options...
justrob Posted January 5, 2016 Author Share Posted January 5, 2016 Tried both SIO ports, couldn't see any broken traces from what I could see under the SIO ports. Guess I'll just wait for the parts and try it after that. Thanks for the help guys. Quote Link to comment Share on other sites More sharing options...
1050 Posted January 6, 2016 Share Posted January 6, 2016 While I wait for parts to come in, are there any alternatives to this diagnosis? Or is this pretty definitvely the cause of my issues? There absolutely is one alternative which does this exact same thing and it doesn't cost much at all to fix it. Squirt some WD-40 into those drive selector switches and work them back and forth twenty times. Now set if for #1 drive and give it a try. I seem to be the only one that needs to do this every ten years or so, but that's the entire fix. It won't fix a bad 3086 which do go bad too though. Contact cleaner is what I have used in the past, but I suspect WD-40 does the same job and is more likely to be at hand. It's certainly easier to find. The rear 3086 handles command and data in/out so it's the first link between the SIO cable and the drive itself. If cleaning switches doesn't fix it outright then I vote for the rear 3086 too. Quote Link to comment Share on other sites More sharing options...
Binarygeek Posted February 18, 2016 Share Posted February 18, 2016 There absolutely is one alternative which does this exact same thing and it doesn't cost much at all to fix it. Squirt some WD-40 into those drive selector switches and work them back and forth twenty times. Now set if for #1 drive and give it a try. I seem to be the only one that needs to do this every ten years or so, but that's the entire fix. It won't fix a bad 3086 which do go bad too though. Contact cleaner is what I have used in the past, but I suspect WD-40 does the same job and is more likely to be at hand. It's certainly easier to find. The rear 3086 handles command and data in/out so it's the first link between the SIO cable and the drive itself. If cleaning switches doesn't fix it outright then I vote for the rear 3086 too. Cleaning the drive head and switch are excellent places to start. I have had this problem on numerous occasions, and have found the most likely candidates are that 1) (The most common one by far:) Track zero is not set correctly and 2) Disk speed is too high. You can tell if the speed is going too fast by lightly putting your finger on top of the disk head while it is attempting to boot. If you read even a single sector, slow your drive down. For the first one, if you have a second bootable drive, try the CPS 1050 Diagnostic and check if track zero is correct. If you don't have another drive, you can adjust track zero slightly in either direction, turn the drive off and on, then try to reboot. Good luck. Rick Quote Link to comment Share on other sites More sharing options...
Kyle22 Posted February 18, 2016 Share Posted February 18, 2016 Before you touch the track zero sensor, blow it out with compressed air. It may only be dirt. If you insist upon moving it, make a clear scratch mark with a sharp dental pick type instrument on the metal frame in front of the sensor so you can put it back in position if necessary. 1 Quote Link to comment Share on other sites More sharing options...
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