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Five 1050's - determining upgrades and diagnostics?


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#1 Sugarland OFFLINE  

Sugarland

    Chopper Commander

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Posted Tue Feb 12, 2019 7:08 PM

I picked up four craigslist 1050's in the past year and have had another 1050 for 25 years (pretty sure it's USD).  Not like I was looking for them. They came with computers. I want to determine the upgrades in them without opening them up if possible. Is there a good way?  The inner shield under the drive mech is a bit of a pain to remove iirc. Any help is appreciated.

 

Photo below. The drive I've had since '94 beeps high pitch when using Spartdos X/U1MB. When turning on the four newer drives, they all make the 'stock' slow head seek sound.

 

I have never used Happy drives but I think they made a program to detect them.

 

Also is there a rom for the 1050 diagnostic cart available?  Would like to check RPMs and head alignment on them with Atari factory disks.

 

I guess booting a DD disk is a start but doesn't specify what's in there.

 

Sugarland

 

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Edited by Sugarland, Tue Feb 12, 2019 7:40 PM.


#2 BillC OFFLINE  

BillC

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Posted Tue Feb 12, 2019 9:10 PM

US Doubler 1050s have a special high speed skew that allows the higher transfer speed without the full track buffer used by many other upgrades.

 

SpartaDOS X and high-speed versions of disk based SpartaDOS can be used to format with this skew, it will fail if the US Doubler upgrade isn't present.

 

The Happy software can be used to determine if the drives have a Happy upgrade.


Edited by BillC, Tue Feb 12, 2019 9:13 PM.


#3 Nezgar ONLINE  

Nezgar

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Posted Tue Feb 12, 2019 9:32 PM

If the shield is still in place, thats usually a good indicator that the drive is still stock. Most people when doing any sort of mod never bother to put the shielding back on. Some upgrades like the original happy boards may not have even fit inside the shield.

First external observation is if it's made in singapore according to the bottom label, it will have a World Storage drive mechanism, with an EPROM and ROM code that has a noticibly faster stepper rate compared to made in Hong Kong drives with Tandon mechs.

As you have observed, the stock 1050 'sio tone' is slightly lower pitch, so that's an indicator it's a stock drive. US Doubler has the same slightly higher pitch as the stock 810 and Happy 1050, but Happy 1050 has minimal delay between each sector due to the track buffer.

The top cover is super easy to remove, so by doing that at a minumum, you can just lift the mech, and shine a flashlight into the shielding to observe the chips and ROM configuration inside through the holes. (turn the room lights off, take a picture through the holes with your camera, if needed, etc)

  • with the drive facing you, the far left chip is the controller chip. Usually a WDC 2793, but sometimes is a 2797 with one pin snipped off. Some stock firmware revisions and speeders don't work with the 2797.
  • next chip is the ROM. Above the ROM you will see jumpers labelled JP1/2/3/4/5/6. There will be jumpers either in the 1/3 configuration for a 2332 mask ROM, or in the 2/4 configuration for an EPROM. Early drives had EPROM's, and later drives seemed to have mask roms. The mask roms are usually the latest 'Revision L' which supports both 2793 and 2797 WDC controllers, but other known versions are E,F,H,J,K. The label may not be apparent, but often has a letter marking written by hand on the label. ICD US doubler would replace this chip with either a mask ROM or an EPROM as well.  If you think you have an oddball configuration, those rev E/F versions are still not found by the community!
  • If the drive is already in the JP2/4 configuration, it's easy to replace the EPROM with a homebrew US doubler.
  • next chip (middle) is the 6507 CPU. Happy, Speedy, Duplicator, remove the CPU and RAM, and plug into the CPU socket. The boards employ a 6502 with extra RAM.
  • Second to right is the 6810 RAM of 128 bytes. Happy requires this to remain in place, even though it adds it's own 6K or 8K of additional SRAM. The US Doubler adds a second 'piggyback' 6810 on top of the first for a total of 256 bytes of RAM for sector buffer for true double density support.
  • last chip on the right is the 6532 RIOT which has 128 bytes of RAM used for the stack, etc.

Latest Happy Utility Software v7.1 is here:
http://atariage.com/...disk/?p=3250240

Atari 1050 Diagnostics Disk is here: (it's a disk, not a cart ROM like the 810 diagnostics)
https://archive.org/...tics_1983_Atari

It's good to pop open the cases to inspect things like the belt condition which often will be stretched or flaking apart if it's been idle for a long time. Because of the belt stretch, the RPM is probably going to be off a good 2-3 RPM, and will float. Also a good time to clean the r/w head with isopropyl alcohol and a q-tip, because in all likelihood, a stock drive has never been cleaned. Lots of other threads on cleaning techniques, but drives that are loud when stepping can often be silenced with a little 3-in-1 oil on the rails.



#4 kheller2 OFFLINE  

kheller2

    Stargunner

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Posted Tue Feb 12, 2019 9:44 PM

If the 1050 drags fail, you have something other than stock.

#5 Sugarland OFFLINE  

Sugarland

    Chopper Commander

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Posted Tue Feb 12, 2019 10:05 PM

Wow Nezgar that is hugely helpful thank you! Regular 3-in-1 household oil? Great. I have some. Not sewing machine oil? I remember that myth but was never sure.

 

Yes I opened them up and cleaned them when I got them. Used 'Swan' 99% isopropyl alcohol on the heads with a qtip. I found the service manual.

 

This evening I opened one up again and yes it's easy to remove the top cover. The front bezel is more tricky. The problem comes with the connectors from the drive mech to the PCB pegs. They corrode and are locked onto the connectors.  It feels like the plastic plug or the pin might break if I pull hard with the pliers. I've done it before and it does come loose but it gives me the eeby jeebies.  I do have some ECG 'industrial contact cleaner with lube' so that should help for the next try.

 

Then the two case locking clips are stiff but even more difficult is getting the pcb into correct alignment with the two white through-hole pegs when putting it back together.

 

The chips you name are under the shield, correct? I can't see clearly through the holes. Yes a camera is a great idea.

 

On one drive I noticed C69 cap has leaked a bit onto the pcb, but the drive still works.

 

All the information you gave is very helpful.  THANK YOU.  Will update here with progress report as soon as possible.

 

Thanks also to BillC and kheller2.



#6 TGB1718 OFFLINE  

TGB1718

    Space Invader

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Posted Wed Feb 13, 2019 8:55 AM

As you have noticed a leaking Capacitor, sounds like a good idea would be to replace all the Cap's in all the drives, else you may end up frying your drives.



#7 xrbrevin OFFLINE  

xrbrevin

    Moonsweeper

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  • Mr Ziggy loves to extend the 1050 heatsink!
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Posted Wed Feb 13, 2019 10:51 AM

set the 1050 drive as D1, connect it but power it off.

load the diagnostic software via a virtual drive using peripheral emulator software and an SIO2PC device, i use aspeqt.

then 'disconnect' the virtual drive and power up the 1050.

start the diagnostic test and it will commence on the real 1050! :) (the atari cant tell the difference!)



#8 Sugarland OFFLINE  

Sugarland

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Posted Wed Feb 13, 2019 12:55 PM

set the 1050 drive as D1, connect it but power it off.

load the diagnostic software via a virtual drive using peripheral emulator software and an SIO2PC device, i use aspeqt.

then 'disconnect' the virtual drive and power up the 1050.

start the diagnostic test and it will commence on the real 1050! :) (the atari cant tell the difference!)

 

Great idea! I used the U1MB's Spartados X then loaded the diagnostic .atr from d2 with d1 being the 1050.



#9 Sugarland OFFLINE  

Sugarland

    Chopper Commander

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Posted Wed Feb 13, 2019 1:03 PM

Since there is not one program or disk to detect more than one (or all) 1050 upgrades I went ahead and took them all apart enough to find out. All the 'new' drives are stock with 1/3 jumper configuration. The two that I removed the shield were the WDC 2793 variants. On the other three drives, I could see through the shield well enough to see the jumpers and no added chips but can't read the chip stamps.

 

The one drive I suspected is a USD is indeed so. Photos below. It also has a darker green pcb. The friend who gave it to me in 1994 though it wasn't USD. :)

 

Thanks again everyone!

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Edited by Sugarland, Wed Feb 13, 2019 1:08 PM.





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