Argh! My new STE may have a DMA issue...

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Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Fri Aug 19, 2016 8:40 pm

So I finally had all the pieces I needed to get the UltraSatan from Lotharek hooked up, the right cable, latest HDDriver, strong micro USB PSU.

So followed the plentiful instructions online but it positively refuses to see any partitions when I allow HDDriver to reboot after creating them.
Tried 3 different 8GB cards, quality genuine Sandisk ones, but no luck.

So I downloaded a test SD card image that has ICD on it already, burnt it with the Mac and booted the STE from it via the UltraSatan.
Happy days, there's the desktop with all the drives and some pre-loaded demos etc.

But...

If I try and copy the 3000+ games files from one partition to another I get a write error after just a handful , a few retries seem to get it moving again ever so briefly, but doing an abort and there are some corrupt looking file names.

Not a happy bunny.

I was tempted to call Brad @ Best as I bought the machine from him and specifically asked *twice* via email if he would ensure it didn't have a dodgy DMA chip to which he told me he runs diagnostic tests (cartridge presumably...) and it would definitely work and only a small handful of early European STE's had the dodgy chip.

So....

I read through this forum and come across Exxos's post about resistors and capacitors and some telling looking Oscilliscope traces.

I don't own a soldering iron since moving to the US and was hoping not to have to buy all that gear again but I'm assuming I don't have much option really? I mean, even if Brad would acknowledge a problematic machine (and I haven't contacted him yet) I don't want a refund, nor do I want to start playing STE lottery with him or ebay, so I suppose I need to try and fix it...

@Exxos:
While your page is informative it's a little confusing as you tried differetn things along the way and conclusions seem mixed...
Based on this image:
Image

Do I just need that big resistor pack and the single black wire?
i.e. I don't need that ceramic capacitor which attaches to the (cut?) 3rd leg?

:shrug:
Last edited by EmpireAndrew on Sat Aug 20, 2016 2:38 am, edited 1 time in total.
1977 VCS Heavy Sixxer (Boxed)
1990 Atari 1040STE, 4MB, UltraSatan, TOS 2.06, TT Touch -> Atari SC1435 Colour CRT Monitor
1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
1993 Atari Falcon030, 14MB, Int 8GB HDD, TOS 4.04 -> Atari PTC1426 Color CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby exxos » Fri Aug 19, 2016 9:23 pm

What DMA chip number do you have in there ?
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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Fri Aug 19, 2016 9:30 pm

I haven't pulled it apart yet...
I'll do that tomorrow morning. Feeling too annoyed at the moment, lol!
1977 VCS Heavy Sixxer (Boxed)
1990 Atari 1040STE, 4MB, UltraSatan, TOS 2.06, TT Touch -> Atari SC1435 Colour CRT Monitor
1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
1993 Atari Falcon030, 14MB, Int 8GB HDD, TOS 4.04 -> Atari PTC1426 Color CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby exxos » Fri Aug 19, 2016 9:34 pm

EmpireAndrew wrote:I haven't pulled it apart yet...
I'll do that tomorrow morning. Feeling too annoyed at the moment, lol!


Theres a whole bucket load of reasons why it can fail. I've been on loop about these issues for ages. It can start with a bad PSU, they are 30 years old etc etc, the SIl resistor is soldered onto the DMA data lines, so you dont need the cap. There are also other resistors on the motherboard which could be a factor, wrong simms could be a factor. the list is endless.

If the DMA chip is in a socket (probably not) you can send it to me for testing. If not, your only option is to ship me the board to test. I am in the UK so thats not going to be cheap.

Personally, if you can't solder then dont mess around with it. If you do make things worse, you could likely need a new motherboard at the end of it all. Food for thought...
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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Sat Aug 20, 2016 2:14 am

I used to be able to solder, I certainly soldered plenty of upgrades onto my STE back in the early 90's, but I haven't done much since.

I saw some of your posts on this subject, maybe there was a tiny batch of faulty chips on some early machines, but other issues are maybe caused by the supporting components and of course with age and faster transfers (these SD cards are pushing the machines to their limits) anything too far out of tolerance is being exposed. I don't know...

I pulled the machine apart this evening so it's certainly not going back to Best now, lol!

I've just dropped $200 on all the tools etc, but it's not clear to me what parts I need to order up.
Is that a 1K or 10K 9 pin resistor pack?
Is it buffered?
I'm having trouble finding the right stuff on ebay.com or amazon.com... :( :shrug:


It all looks good to my untrained eye, no leaking caps, no swelling caps etc etc.
All very clean actually.

I took some photos.

Revision:
Image


Full board:
Image


TOS area closeup:
Image


Socketed chip 1:
Image


Chip on mainboard:
Image


Socketed chips:
Image


What bodge is this?!
Image


1MB SIMM - 8 chip, all 4 identical:
Image


PSU 1:
Image


PSU 2;
Image


PSU 3;
Image
1977 VCS Heavy Sixxer (Boxed)
1990 Atari 1040STE, 4MB, UltraSatan, TOS 2.06, TT Touch -> Atari SC1435 Colour CRT Monitor
1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
1993 Atari Falcon030, 14MB, Int 8GB HDD, TOS 4.04 -> Atari PTC1426 Color CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby TheNameOfTheGame » Sat Aug 20, 2016 3:58 am

Sucks...from your pictures you have the bad dma chip (TOS Area Closeup picture) - C025913-38 == bad, C398739-001A == good. Your picture shows C025913 :(

Looks like Best did you wrong. They need to replace the computer or the chip. Or you can replace it since you have the tools now. But dropping $200 to fix Best's mistake...damn.

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Re: Argh! My new STE may have a DMA issue...

Postby exxos » Sat Aug 20, 2016 7:55 am

I really wish people would stop calling the -38 bad! Its just not true. I've had more problems with the 001A. So C025913-38 == good, C398739-001A == bad from what I have seen. Please stop spreading the -38 bad myth!

As for the resistor, its a 2.2K 9 pin sil array. Also what are the numbers on the sil arrays around the 68000 CPU ? (3 red 3 black)
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Re: Argh! My new STE may have a DMA issue...

Postby troed » Sat Aug 20, 2016 8:05 am

Fwiw - I bought an STE from someone who had the "bad" DMA, specifically to test if exxos' fix would solve it. The previous owner used it with UltraSatan and had lots of issues like you describe.

I have another DMA device (Alan H's Unicorn) and no matter how much I've tried to provoke the error it hasn't shown up even once.

So, we might be talking about a UltraSatan problem more than a DMA problem.

/Troed

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Re: Argh! My new STE may have a DMA issue...

Postby exxos » Sat Aug 20, 2016 8:18 am

troed wrote:So, we might be talking about a UltraSatan problem more than a DMA problem.
/Troed


It has crossed my mind there there could be a faulty batch of UltraSatan. No way everyone under the sun who uses UltraSatan has "DMA issues".

Clearly as you tested that machine from the last guy who had the same issues and found no problems, that it can't have been the STE itself to blame for the failures.

EmpireAndrew wrote:So I finally had all the pieces I needed to get the UltraSatan from Lotharek hooked up, the right cable, latest HDDriver, strong micro USB PSU./Troed


The PSU could may well be to blame. A lot of bad regulated cheap china junk isn't going to power the hard drive very well. SD cards are very sensitive to noise. Try a decent PSU, try a different card.

When and where did you buy your US from ?
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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Sat Aug 20, 2016 1:32 pm

I'm not inclined to say that Best did wrong as although I did ask re the DMA chip bad/good and didn't get a direct answer (which I noted to myself at the time) I was told the machine would be tested to confirm it didn't have a bad one. Regardless of the number printed on it.
Unfortunately I don't have an old Atari megafile to test it with, I only have the UltraSatan. I have a Gigafile but that's in the TT and therefore I didn't order the external ACSI cable for it.

But this morning I tested the Ultrasatan with the same psu (Anker 2.1Amp) and high quality micro USB power cable (Anker) and the same SD Card by using it on the TT and it works flawlessly. Well, it passed the initial tests, partitioning it, copying some files to it from a floppy, reboots etc etc.
I'm re-imaging the test card from the Mac now (with the hundreds of games etc pre-installed) and will bulk copy from one partition to another.

But sadly, it seems the Ultrasatan and supporting pieces work fine, the issue is with the STE.
Maybe it would work with a slower ye olde hard drive, maybe not. I can't say. But it isn't working with this Ultra Satan which works on my TT and we know TT's don't have any DMA issues so whether it's the chip, board noise or whatever, Atari messed something up somewhere..
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1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby frank.lukas » Sat Aug 20, 2016 3:12 pm

My experience is put the right STE/TT DMA Chip (C398789-001A) in the 1040STE and the problem is solved.
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Re: Argh! My new STE may have a DMA issue...

Postby troed » Sat Aug 20, 2016 3:46 pm

frank.lukas wrote:My experience is put the right STE/TT DMA Chip (C398789-001A) in the 1040STE and the problem is solved.


I agree - I think it will. I also think a lot of other things might solve the problem. Including redesigning UltraSatan. (As I wrote above, on a proven faulty STE+UltraSatan combo, where the US worked fine on another STE, my Unicorn worked fine on the first STE. Apparently the DMA device is heavily involved on whether there's a problem or not)

/Troed

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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Sat Aug 20, 2016 4:17 pm

So the question is, what is the "spec" for ASCI and what is in spec and what is out of spec?
And can some peripherals be out of spec but work if the ST is tolerant enough? Or is the circuit design and tolerances of the STE causing it to go out of spec?
1977 VCS Heavy Sixxer (Boxed)
1990 Atari 1040STE, 4MB, UltraSatan, TOS 2.06, TT Touch -> Atari SC1435 Colour CRT Monitor
1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
1993 Atari Falcon030, 14MB, Int 8GB HDD, TOS 4.04 -> Atari PTC1426 Color CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby frank.lukas » Sat Aug 20, 2016 4:37 pm

-> http://phoenix.inf.upol.cz/~opichals/li ... P&index=57

Use the Google Translator !

    Sehr oft werde ich gefragt warum nicht der C025913-38A als DMA-Chip
    in der Liste steht. Die Antwort ist ganz einfach, der 520/1040STE,
    MegaSTE und TT030 haben eine geänderte ACSI-DMA Schnittstelle und
    in den vorhin genannten Computern arbeitet nur der C398739-001
    bzw. C398789-001A (DMA-Chip STE (U300)) als DMA-Chip einwandfrei.

    Folgende Symptome lassen auf einen C025913-38 /-38A als ACSI-DMA-
    Controller schliessen: Mitten im Formatiervorgang wird die Mel-
    dung ausgeben die Diskette sei schreibgeschützt.
    Schreibzugriffe auf eine oder mehrere angeschlossene Festplatten
    enden mit Datenverlust, Lesezugriffe funktionieren aber!
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Re: Argh! My new STE may have a DMA issue...

Postby TheNameOfTheGame » Sat Aug 20, 2016 5:00 pm

exxos wrote:I really wish people would stop calling the -38 bad! Its just not true. I've had more problems with the 001A. So C025913-38 == good, C398739-001A == bad from what I have seen. Please stop spreading the -38 bad myth!

As for the resistor, its a 2.2K 9 pin sil array. Also what are the numbers on the sil arrays around the 68000 CPU ? (3 red 3 black)


Yes, I realize the work have done, but the quote C025913-38 == good, C398739-001A == bad is not from me, it is from Jookie's site http://joo.kie.sk/?page_id=250

EmpireAndrew wants to use an ultrasatan then he probably needs the C398739-001A dma chip.

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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Sat Aug 20, 2016 6:14 pm

The translation says you need the 001 for the Ultrasatan as the 38 has problems.
I don't know if that's simple parroting the commonly held belief though.

Let's turn this around...

1. Does anyone have an Ultra Satan working on the 38 chip?
2. Has anyone with a 001 chip ran into problems with an Ultra Satan?

And where do I get an 001 chip from *if* necessary?
I don't see them listed on here, at Best or ebay (even ebay Germany)...

** EDIT:
Is this it on the Best site?
C398739 160511 (STE / MegaSTE / TT DMA 40 pin Dip) $59.00
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1990 Atari 1040STE, 4MB, UltraSatan, TOS 2.06, TT Touch -> Atari SC1435 Colour CRT Monitor
1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
1993 Atari Falcon030, 14MB, Int 8GB HDD, TOS 4.04 -> Atari PTC1426 Color CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby exxos » Sat Aug 20, 2016 6:28 pm

EmpireAndrew wrote:1. Does anyone have an Ultra Satan working on the 38 chip?


Yes - several machines.

EmpireAndrew wrote:2. Has anyone with a 001 chip ran into problems with an Ultra Satan?


Yes, even did a video on it.
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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Sat Aug 20, 2016 6:41 pm

OK, so here's the plan of action then...

1. Try the resistor pack. If it works, job done.

2. If (1) doesn't work, replace the DMA with an 001 version in a socket. Then send the 038 to Exxos for his collection for analysis (assuming he's interested, otherwise it goes in the trash).


So these are the right resistors yes?
http://www.ebay.com/itm/100-pcs-4609X-1 ... xy-HtRXltn


Is it worth me buying any other values as well in case?

I assume I need wire to solder the common pin in that pack to the resistor leg in your pic.
Nothing is cut right?
Last edited by EmpireAndrew on Sat Aug 20, 2016 6:43 pm, edited 1 time in total.
1977 VCS Heavy Sixxer (Boxed)
1990 Atari 1040STE, 4MB, UltraSatan, TOS 2.06, TT Touch -> Atari SC1435 Colour CRT Monitor
1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
1993 Atari Falcon030, 14MB, Int 8GB HDD, TOS 4.04 -> Atari PTC1426 Color CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Sat Aug 20, 2016 6:42 pm

Although I would expect the PSU to be fine is there any test I can do with a multimeter?
1977 VCS Heavy Sixxer (Boxed)
1990 Atari 1040STE, 4MB, UltraSatan, TOS 2.06, TT Touch -> Atari SC1435 Colour CRT Monitor
1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
1993 Atari Falcon030, 14MB, Int 8GB HDD, TOS 4.04 -> Atari PTC1426 Color CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby exxos » Sat Aug 20, 2016 8:39 pm

Those are the packs yes. and please do save the -38.

I would be interested in knowing the 6 resistor pack values (3 black and 3 red around the cpu also). We need to make sure your motherboard has all the same values as mine do.
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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Sat Aug 20, 2016 9:08 pm

As far as I can tell the black ones are all the same:
Image

Image


The reds are hard to see as the labelled side is annoyingly facing the chip sockets etc:

Here's the left end of one:
Image

And the right end of its neighbour:
Image
1977 VCS Heavy Sixxer (Boxed)
1990 Atari 1040STE, 4MB, UltraSatan, TOS 2.06, TT Touch -> Atari SC1435 Colour CRT Monitor
1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
1993 Atari Falcon030, 14MB, Int 8GB HDD, TOS 4.04 -> Atari PTC1426 Color CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby exxos » Sat Aug 20, 2016 9:22 pm

If you can, I would change them all for 2.2k ones. Also there is one which I cant see exactly, in front of the cpu (red pack) that should be 1.2k.
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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Sat Aug 20, 2016 9:44 pm

I can't see it either, it's so close to the socket. I don't want to bend it back and forth in case I break it.

You'd change the 3 red and the 3 black to 2.2k?

What are they all now?

And what's the logic behind changing them? I read your stuff on the resistor pack for the DMA chip, but I must've missed the info on why I'd change these ones?
1977 VCS Heavy Sixxer (Boxed)
1990 Atari 1040STE, 4MB, UltraSatan, TOS 2.06, TT Touch -> Atari SC1435 Colour CRT Monitor
1991 Atari TT030, 2/64MB, Int 8GB Gigafile SCSI2CF, TOS 3.06, CaTTamaran Accelerator -> Atari TTM195 19" Mono CRT Monitor
1993 Atari Falcon030, 14MB, Int 8GB HDD, TOS 4.04 -> Atari PTC1426 Color CRT Monitor
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Re: Argh! My new STE may have a DMA issue...

Postby exxos » Sat Aug 20, 2016 10:59 pm

EmpireAndrew wrote:I can't see it either, it's so close to the socket. I don't want to bend it back and forth in case I break it.

You'd change the 3 red and the 3 black to 2.2k?

What are they all now?

And what's the logic behind changing them? I read your stuff on the resistor pack for the DMA chip, but I must've missed the info on why I'd change these ones?



Its a theory on why I never have any DMA problems when everyone else does. Though I never had a problem with the -38s so someone needs to try this stuff out, only then I can document it.

Currently everyone just puts a 001 in there and never bothers to find out the real reason why it solves the problem for them. The 001 doesn't even fix everyones issues anyway. These type of posts appear almost on a weekly basis, I keep repeating myself over and over. So unless people quit with the 001 as a universal fix for everything and actually investigates it for a change, then the actual cause of dma problems will never be found. I've done all I can, I've pretty much never seen a bad dma board. So unless people start helping then there is no more work I can do.
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EmpireAndrew
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Re: Argh! My new STE may have a DMA issue...

Postby EmpireAndrew » Sat Aug 20, 2016 11:36 pm

So you always put 2.2k's in to replace the red and black ones?
But I take it that in itself doesn't necessarily fix the issue or you wouldn't be adding a resistor pack to the -38?

And I agree, it would be good to know what is different about the 001 that (mostly?) fixes people's problems. Atari obviously switched to it for a reason, but maybe it simply tolerates some other underlying issue with the board design better than the 38?.

Frankly, I just want it working. I spent a lot to get this STE as I wanted as close to perfect as I could get so I could just go ahead and enjoy the machine. So it's frustrating to have to perform surgery on it.
But I'd like to know why whatever fix I do actually fixes it. Ridiculous that 25 years on we don't have an answer.
But there will be a limit on how much investigation I am prepared to do, in any case I don't own a scope or anything so there isn't much I can do anyway.

I think I'll start with the resistor pack on the 38, after all the only other option is to replace it anyway so I'm still faffing with it regardless.
If that doesn't work I'll probably swap it out tbh.

And if that doesn't work then I'll put a resistor pack on the 001.
Only then will I mess with the rest of the board (i.e. the other resistor packs).

The less I mess with the board itself the better. Less chance of screwing up.
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