Atari 810 Disk Drive Boot Error Problem

[PileofBones72]

Hello All. I'm Sure there are a million threads on this Subject and I'm Beating a Dead Horse. I picked up a Atari Bundle from some Older Family friends and ended up, among other things, Two 810 Disk Drives. After testing them both, 1 works, 1 Gives a Boot error on Start-up. I went on to clean them and do maintenance on them. The Non-Working Drive, I have: Cleaned the Head, Cleaned and Lubed the Rails, Cleaned the Drive Selection Switch using contact cleaner, Cleaned the Obvious Plug-In Connectors with contact cleaner, Checked the Belt ( it was fine ) and oiled the Motor Bearings and worked them manually but, to my disarray, Still am getting " BOOT ERROR " on startup. I then went on to set it up as drive 2, Booted up with Drive 1, and tried to Format on it. The Head started to move as it should, got about halfway across the disk, Stopped, and just made the Classic BRAPPP...Noises. No go there. These are the first 810 drives I've had and am not Familiar with them. Any Pictures on what to look for, Suggestions or Advice would be greatly Appreciated. I will Attach a Couple Pics I took while Performing Maintenance to give you a idea of what I Have. Thanks Again.

[Germancar]

Can you verify the running speed is super close or right on 288 RPM?

 

 

[TGB1718]

As it appears the visible IC's are socketed, there may be some oxidation in the pins, so try gently easing them up (usually a push down first)

then ease up a bit and finally push in again (all IC's).

 

Also have you checked the DC voltages, I don't have an 810, but assume it produces +5VDC +/- 5% and +12VDC +/- 5%.

 

I know you've cleaned the head, but I've done the same on a 1050 and thought it looked ok, but had similar problems to you,

I went back and did a second clean and it's been fine ever since, must have been something still on the head that wasn't visible

to the naked eye.

[TZJB]

18 hours ago, PileofBones72 said:

Hello All. I'm Sure there are a million threads on this Subject and I'm Beating a Dead Horse. I picked up a Atari Bundle from some Older Family friends and ended up, among other things, Two 810 Disk Drives. After testing them both, 1 works, 1 Gives a Boot error on Start-up. I went on to clean them and do maintenance on them. The Non-Working Drive, I have: Cleaned the Head, Cleaned and Lubed the Rails, Cleaned the Drive Selection Switch using contact cleaner, Cleaned the Obvious Plug-In Connectors with contact cleaner, Checked the Belt ( it was fine ) and oiled the Motor Bearings and worked them manually but, to my disarray, Still am getting " BOOT ERROR " on startup. I then went on to set it up as drive 2, Booted up with Drive 1, and tried to Format on it. The Head started to move as it should, got about halfway across the disk, Stopped, and just made the Classic BRAPPP...Noises. No go there. These are the first 810 drives I've had and am not Familiar with them. Any Pictures on what to look for, Suggestions or Advice would be greatly Appreciated. I will Attach a Couple Pics I took while Performing Maintenance to give you a idea of what I Have. Thanks Again.

 

Thanks for the pictures.

 

This looks to be an 810 Revision 3 in very good condition and has a different Rear Board layout and mechanism (I think) to your other, working, 810 disk drive.

 

The Rear Board supplies +5V, +12V and a negative unregulated supply which supplies the CR108 power LED at -5V regulated by the CR107 5V1 zener diode and R132 330R current limiter all on the Side Board.

 

It is unfortunate that there are so many boards with connections going in and out of one another. Also the connectors are inconsistently numbered such that J106 connects to P101?

 

 

 

I have attached the Field Service Manual for Atari 810 Revision 3: Atari810ServiceManualRev3.pdf

 

 

 

 

[PileofBones72]

I do not know how to test the speed of the drive. I haven't checked Voltages yet. Thanks for the service manual, perhaps this can Shine some light on things! 

[+kheller2]

I don't recall you stating if you could read a disk that already had data on it.  if you can, there are several RPM testing programs.

 

[Germancar]

I agree with checking voltages with a meter, reseating chips and connectors, including the sideboard's large connection, etc..

I would also advise getting some DeOxit D100L from Amazon or something to use on all connections.

 

SMARTDOS has a drive speed check right on the menu. To speed check, maybe try:

 

Hook up both 810's with your good one as drive 1 and the troubled one as drive 2.

Boot from SmartDOS on your good 810, format a blank disk on your good 810 and then place the newly formatted disk in drive 2.

Choose the Speed Check menu option from SmartDOS and see if drive 2 can read it or get a speed check. 

 

That "Grass Valley" board on top of the rails is the bit that should hold the drive to about 288rpm.

 

SmartDOS: https://atariwiki.org/wiki/Wiki.jsp?page=SmartDOS

[+Larry]

I've had a couple of 810's that had bad Floppy Disk Controllers.  If checking the speed and cleaning the chip contacts fails, consider the following:

 

1. Can the "bad" drive format a blank disk and write Dos to it?  If so, can it then boot its own just-written disk?  Drive may be out of alignment.  Boot from good drive as D1:, set bad drive as D2:.  Format a disk in D2: and write Dos to it, if it will do that.  Set the bad drive to D1:  Take the good drive out of the chain.  Attempt to boot the bad drive with its just-written disk.

 

2. If #1 fails, consider carefully swapping chips between the "good" and "bad" drives.  I would start with the 1771 FDC.  I think that is the most likely culprit.  If the 6507 cpu or rom had an issue, I don't think the drive would even try to boot.   Realize before you start there is a small chance that you could damage a "good" chip by putting it in a "bad drive."  Make sure that both chips are the same before swapping.

 

3. (Edit)  Another thing to try if the above fail is to swap the mechs (assuming they are the same type) and see if it is the mech rather than the circuitry.  I've seen that happen on 810's, too.  B&C used to sell replacements for $40 (last time I looked).  If the drive is out of alignment, that might be your best path. 

 

 

[PileofBones72]

All Great Info Guys! I'm Hoping to finally get a little more time to tinker with it this weekend. I'll keep you updated, Thanks Again! 😁👍

[PileofBones72]

Ok Guys, Finally got back on this project. I Disassembled the " Bad " 810 drive Cleaned and Reseated all the Chips and Connections. I hooked it up to my 130XE with my Indus GT as Drive #1 and the 810 as Drive #2. Long Story Short, it started out acting very Hokey. Sometimes it would Format, sometimes it wouldn't. Sometimes it would Format and Write, sometimes it wouldn't. Finally got it to Format, Write and Read. I booted it back up as Drive #1 and it would load Dos 2.05 halfway, stop, let out a grunt, the head would move back and forth, then it finished loading it. Finally, I felt like I was getting somewhere. I put in a copy of SmartDOS and it did the same, Loaded Halfway, Grunted, Head Moved back and forth, then finished loading. I have been running the Speed Test from SmartDOS on it now for about a half hour and it holding 288RPM's. Gonna let it go for awhile, hoping the Ole' Girl just needs to finish waking up! I will keep ya'll updated. I really do appreciate all of your comments and help! Fingers Crossed!🤞 😁