1050 drive issue

[+Nezgar]

SNES PSU works fine if you do the 1050 green mod - where you swap out the 78xx voltage regulators for switching types (also known as 'buck converters')

 

http://www.mathyvannisselroy.nl/Atari%201050%20goes%20green.htm

Woops, you're right. I missed that SNES PSU outputs DC, not AC.

[_The Doctor__]

Sourcing 9VAC supplies with greater than 1A has come up a couple times in the forums. Ask around your local electronics stores if they carry a 9V AC supply of 2A or greater. Here is a prior thread where I found one this way: http://atariage.com/forums/topic/277382-atari-1050-in-kinda-rough-shape/?p=4000363

 

Only problem is it came with a 2.1mm barrel connector, and 1050 needs a 2.5mm, so I replaced the end on the cable. Then I discovered adapters for such a situation: https://www.ebay.ca/itm/152348446057

 

Apparently a 1.3A SNES PSU also works. (has got to be borderline sufficient imho)

 

But then again, just getting an original one is the least time consuming and brain consuming.

SNES??????? NOOOOOOOO, that's DC! you would have to modify the 1050!

[xrbrevin]

all my snes/nes adapters are AC - i wonder if the European ones are diff'rent to the USA ones?...

[_The Doctor__]

I am looking at one that is labeled for SNES and it is AC in and DC out for USA version... are you sure it's AC in AC out elsewhere?

Edited July 15, 2018 by _The Doctor__

[+Nezgar]

Sure enough some brief googling found me an NES schematic: https://console5.com/techwiki/images/5/58/NES-001-Schematic---Power,-AV,-RF-Switch.png

Shows a full bridge rectifier, with 7805 regulator. So technically, original NES will work with an AC or DC supply.

 

an SNES schematic: https://console5.com/techwiki/images/d/dd/Snes_schematic_color.png

shows no bridge rectifier, only some capacitors, a polarity protection diode, and a 7805 - so SNES is DC Only.

 

Hopefully explains some of the confusion...

[Keneg]

I checked voltage at the power switch tonight. Power off ~11.5 VAC. Power on, after initialization, less than 5 VAC. Definitely 1 amp is not enough.

[Keneg]

Hey Keneg, I don't think you've mentioned here yet what type of power supply you're using on the drives, or if you've yet measured the 3 different power rails, with and without load (IE with disk spinning): 9VAC, 5VDC, and 12VDC

 

Your symptoms almost sounds like that of an underpowered drive I tried to run off of a 1Amp 9VAC supply. That one had enough for the drive to POST and respond to SIO, but not enough to operate when spinning the disk.

Thanks Nezgar! I received a true C017945 adapter today. One of the drives now seems to work fine. I was able to format a disk, transfer DOS files and then boot off it. I realize it could still be misaligned, but that probably doesn’t matter to me. I just want to create disks using RespeQT and a true Atari drive so I can experience what it was like back in the 80s. I am returning the 1 amp adapter. Very upset that the seller mislabeled his adapter.

[_The Doctor__]

you have two mechs, 1 of them will probably be ok as far as alignment goes.... you may run into original disks in the future you wish to load or your disks may make it out into the world some day.... so I vote for using the best you have. Chances are if it formats both single and enhanced as well as booting writing and reading from both densities the drive should be pretty darn close.

[Keneg]

I plan to buy a diagnostics disk from Best Electronics. If the drive reads it, the alignment should be close enough.

[+Nezgar]

Keneg, good to hear a good power supply solved your problems! And that my hunch on your symptoms was on the mark.

 

I have acquired a number of 1050's over the years, and honestly I've never had to adjust the alignment on any of them, so I wouldn't worry about that. Most issues with 1050's I've solved with lubrication, belt replacement, cleaning, and chip replacement. If you can format a disk in one drive, and read/write it OK in a different drive, you should generally be OK. Ability to read a commercial disk is another hint your alignment is OK.

 

The 1050 diagnostics disk from BEST is the same test program that you've already been using from earlier in this thread. The alignment disk from BEST is only useful if you have an oscilloscope as well.

 

Cheers, and enjoy!

[Keneg]

Tonight I made a full DOS 2.5 disk and managed to duplicate a disk. I was trying and failing to duplicate the diagnostic disk, but then I noticed it was a 512 kB sector HD image. Doing a 90 k image worked fine.

[E474]

Hi,

 

I've just tried the 1050 Disk Diagnostics (1983).atr (posted earlier in this thread) with a drive I've just got off eBay. The drive passes the Diags (1), and works fine with the Trouble Shooting (2), Single density burn-in 10 minutes (option 4). I want to run option 5, Double density burn-in, 2 hours, but the software acts a bit weird. I have to type in the serial number (10 digits, leading zeroes required), so I type in the serial number (I assume it is not starting with 7VDFF), but when I type in the serial number, the software just prints "End of Diagnostic Testing", "Do you want to Run Diags (1) or... ", but the drive is either formatting the disk, or doing a read/write test. This lasts for about 3 minutes, the drive stops spinning for about a minute, then starts spinning for a minute, stops spinning for a minute, etc., etc. I've left it running, but there seems to be no way to get the status of the burn-in back to the Atari Diagnostic program, is this normal? Also, by double density I'm assuming it means enhanced density, e.g. 1040 * 128 byte sectors.

 

Drive itself seems fine, and was bought as a stock 1050, no modifications/upgrades, so I could install a BitWriter Replica into it. Can anyone comment on using this burn-in test, or recommend a similar test/diagnostic program, I want to make sure the drive is good before upgrading it?

[+Nezgar]

I think it's trying to print to a nonexistent printer, so it's stalling and timing out each time it tries to print a line. Maybe you can enable printer emulation in AspeQt or whatever you're using for SIO2PC?

 

I would just run a whole disk sector copier repeatedly to read/write the same disk (filled with data) over a period of time if you want more confidence of reliability. The reads and writes should be a constant rate, if you hear hesitations between sector read / write intervals, something may be up with the drive, or the disk

 

I like MyCopyR. If you have more than 64K in the computer, you can read a full disk in 1 pass too.

 

Stock 1050 'Double Density' is indeed 1024x128b sectors, aka Dual or Enhanced. Technically it can be called such because it uses MFM encoding instead of FM...

[+kheller2]

I haven't found a complete 1050 FSM online yet (some are missing large sections). I did found one that included the diag section using the floppy: (hand typed, typos are mine)

 

Single density burn in (10 min)

This is a short test to check compatibility between drives. A failure on this test indicates and alignment problem. This test first writes to all sectors pattern E5 then does a read of all sectors. Be sure to use reformatted diskette #FD100026.

 

Double density burn ing (2 hours)

This test formats the diskette in double density, writes and reads all data fields with a sequential seek, and writes and read all data fields with an accordian seek.

 

Errors are logged into the first and third sector on the track where they occur. These errors can be printed out on the printer using the printout option in the troubleshooting options of the diagnostic test program.

 

If the 1050 should be disconnected from the SIO line once this test has been started the testing will continue until the pass counter reaches zero. The test will abort if: The drive fails to format or verify format, the drive fails to read or write the error logs (sectors 1 and 3 on each track), more than 128 errors occur in any one sector.

 

Error printout...

This option is used with the above test to printout the error logs on each track.

 

You can read the rest in this PDF:

 

http://www.atarimania.com/documents/Service_Manual_for_the_Atari_1050_Disk_Drive.pdf

 

 

[Kyle22]

That's a jpg, not a pdf.

[xrbrevin]

copy the link and paste it into the address bar but change .jpg to .pdf before pressing enter

[+kheller2]

fixed.

[_The Doctor__]

who will stitch all the pieces together for a complete FSM?

[E474]

Hi,

 

I didn't realise the diagnostic disk was to be used with the Field Service Manual, so didn't know about printing the error listing (stored on the burn-in disk). I'm using sio2bsd on a Raspberry Pi to emulate a 1050, so I loaded the diagnostic disk with:

 

sio2bsd 1050\ Disk\ Diagnostics\ \(1983\)\(Atari\).atr

 

When the diagnostic disk had booted up on the 8-bit, I killed the sio2bsd process with Control-C, powered up the new 1050 as drive 1, put the double density (enhanced density) burn-in disk in the 1050, and restarted sio2bsd to act as a printer (only) with:

 

sio2bsd -t -p ~/printer.txt -

 

The output of printer.txt looks like:

1050 BURN-IN (2HR), REV.A               



SERIAL I.D. = XXXXXXXXXXX                

PASS COUNTER = 24                       
PASS COUNT RECEIVED = 24                

NO ERRORS-ALL TRACKS 

(I've masked the actual serial number with X's).

 

Given it has passed all the Atari Trouble Shooting tests, I think the drive is in good working condition.

 

I didn't realise there were various different FSM's/SM's on the net - I had a quick look, and this one looks complete (in terms of sections present, etc.):

 

http://www.jsobola.atari8.info/dereatari/literatdere/1050fsm.pdf

 

I think for this PDF, the original FSM has been scanned/OCR'd and some screens captured (it's also a searchable PDF), if you have a look at the table of contents, it looks like the one I have linked to above is reasonably complete, apart from the "service bulletin" section. Obviously it would be nice to have a scanned original.

 

Thanks a lot for your help!

[Keneg]

I got in the 6532 chip and replaced it. It still didn’t work. Since I now hav3va good drive I formatted a disk and transferred the DOS files. I then put it in the dead drive and tried to format it. Failed with error 173. Put it back in the good drive and all of the files are still there, so it seams like the head isn’t erasing or writing to the disk. I took a good look at the head. It is shiny with no indication of wear. I know that doesn’t rule out an internal fault, but it may indicate that the head isn’t receiving the signals it is supposed to. Since I now have the shields off, I guess I will check voltages at some of the test points.

[_The Doctor__]

make sure connector to the header pins on pcb is lined up correct and no wires are broken on connector, location front of drive right hand side...

[Keneg]

Ok, I have had that off and on twice. I am fairly certain it is on correctly, unless it was wrong when I received the drive. I will try checking continuity of the wires.

[1050]

I got in the 6532 chip and replaced it. It still didnt work.

But now it's not doing the flashy thing with the busy

light either right?

 

Thanks to you and Nezgar, flashy busy light gets a

new first item to check - the power supply.

 

173--BAD SECTORS AT FORMAT TIME

 

Huh, that sounds about right then. Symptoms are now

lining up with no power to erase/write with. And I

helped a guy thru that one with success too. Just

have to find the thread so you can do further studies.

 

http://atariage.com/forums/topic/239200-another-strange-1050-fault/

 

Quietly sitting debating on if any other advice could

be added and a thought crosses my mind. Could the

exposure to a weak sauce power supply damage a 3086

involved with erase/write Bias power generation?

Which came first the chicken or the egg sort of a

deal.

[Keneg]

If I rad that thread correctly, at least part of the problem was a bad 3086 chip. I have 5 of them ordered. They arrived at USPS in Chicago from China on the 25th.

[Keneg]

Got in my 3086 chips and replaced the two I found. No change in the symptoms. I checked some voltages. At the power switch I get 10.18 VDC when off, but only about 5 VDC when turned on. I checked voltages at the regulators and got 12, 5, and 2 VDC. TP13 had around 5 while I had nothing at TP15. I need to get some mini clip on leads. It scares me trying to read voltages with my leads. Afraid I will short something out.