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JDW

SE/30 PDS Adapter Epic Blunder

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4 hours ago, james_w said:

@Bolle @JDW I have re-tested (with a less sleep-deprived brain) with my Turbo 030 and all is fine with the ProtoCache card :-) So at least I didn't screw *everything* up!

 

James, I know you know *a lot* more about electronics than I, so I think I've got an even smaller chance than you of rectifying my mistake. I'm working through getting over it.

Your statement above means you confirmed your TS Adapter is undamaged, correct?

 

There are varying degrees to electronics knowledge even among electrical engineers, and I give the humble nod to @Bolle as being far more practically savvy when it comes to vintage computing repairs.  Indeed, that is why I have obtained his very kind permission and cooperation to ship my TS Adapter and Turbo 040 (alongside 2 other boards) to him for detailed examination.  Bolle has the means to test the TS Adapter whereas I do not.  He also has some ideas about a possible chip-swap fix if my 040 is determined to be damaged.  My hope is that his findings can help you and others who find themselves newly initiated into our growing Epic Blunder Club.  

 

When doing a lot of parts swapping and testing in a vintage Mac (like my SE/30), the human brain can get so focused on doing things quickly it forgets the basics like never plugging in an accelerator PDS card into the top connector of the TS Adapter.  It's a blunder just waiting to happen to anyone, not just those of us with the name "James W." 

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Quote

Your statement above means you confirmed your TS Adapter is undamaged, correct?

I don't have a TwinSpark adapter, mine is one of the ones that @Bolle kindly made and sold a couple of years ago. But yes, I've confirmed it is undamaged. Phew!

 

11 hours ago, JDW said:

My hope is that his findings can help you and others who find themselves newly initiated into our growing Epic Blunder Club.  

I hope so too! Turns out you and I have different generations of Turbo 040 so the fixes (if hopefully figured out) will probably be different. I've learned you have a later board with one big ASIC, whereas I have the early board that is covered in chips, presumably all integrated into the ASIC later on. Mine is only 25mhz but does at least have the bolt-on cache card.

 

11 hours ago, JDW said:

When doing a lot of parts swapping and testing in a vintage Mac (like my SE/30), the human brain can get so focused on doing things quickly it forgets the basics like never plugging in an accelerator PDS card into the top connector of the TS Adapter.  It's a blunder just waiting to happen to anyone, not just those of us with the name "James W." 

Totally agree! I was rebuilding an SE/30 from scratch and then troubleshooting some memory that I wasn't too sure was reliable so I'd pulled the motherboard countless times in one evening. It's a shame the stakes are so high when working with old and rather rare bits and bobs...

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Your Twinspark is still working fine, the Turbo040 however is shot.

I do get instant death chimes when turning on the IIci with it plugged in.

 

When measuring resistance to ground on the pin that got hit by 12V on the ASIC I get around 1k while on mine this is somewhere in the megaohms.

Even on some surrounding pins the resistance to ground is very low while on mine they are not. This indicates that something inside the chip shorted out.

 

Getting a replacement is going to be near impossible... some of those wonky chinese chip-trading-reseller-whatever sites say they stock a small amount of those.

@JDW care to send them an inquiry and see if they actually stock them? Chances are they are fakes, but that would be a weird part to fake as probably nobody ever is going to need one of those ever, except you :tongue:

Part number for the chip is VY14676 and a google search will turn up two sellers.

 

Not sure if I am brave enough to swap in my ASIC just for testing :/

 

Edited by Bolle

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I put out some requests for VY14676-2 from some US sellers about a year ago.  Out of several, two responded, but both required $50 minimum order.  I am super curious if they are legit.

 

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4 hours ago, joethezombie said:

$50 minimum order

Most important question: how many chips would you get for $50?

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Hm, might be different if we split the risk?

Let‘s see what @JDW says. I’d throw in some cash as well for a few chips.

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On 1/18/2020 at 3:39 PM, Bolle said:

Hm, might be different if we split the risk?

Let‘s see what @JDW says. I’d throw in some cash as well for a few chips.

If that reply to @joethezombie was 1 year ago, another reply back to them should be sent to confirm they still have them.  I would also suggest asking them how they managed to get their hands on so many "Daystar" chips, if indeed they really are official Daystar chips.  If they claim they are indeed Daystar chips, then they should be able to answer the question, "how were they used."  If they reply "accelerator cards," then perhaps the chips are legit. 

 

I've bought version-C 68030 CPUs from China before with success, but VLSI chips specific to a smaller manufacturer like Daystar is something altogether different, so we have to be careful here and do our best to confirm they are indeed what we need.

 

The chip we are talking about is the big one show in my photo here:

 

DayStar_68040_40MHz.jpg.0dc77448e3a6e6b17b4fe80e4509d930.jpg

 

If indeed that VLSI chip is bad and if replacing that one chip would fix the card, assuming the Chinese chips are legit, it's worth buying them to replace the chip, especially since @james_w would need one too, seeing he did exactly the same thing I did.  This is assuming he has the same 040 card that I do, shown in the photo above.

 

 

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5 minutes ago, JDW said:

especially since @james_w would need one too, seeing he did exactly the same thing I did.

He however has the older Turbo 040 revision that does not have the ASIC but a lot of GALs instead. Totally different story.

There are going to be at least one (maybe more) dead GALs on there.

 

However keeping a few of those ICs around if they are legit might still be a good thing just in case.

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5 minutes ago, Bolle said:

He however has the older Turbo 040 revision that does not have the ASIC but a lot of GALs instead. Totally different story.

There are going to be at least one (maybe more) dead GALs on there.

 

However keeping a few of those ICs around if they are legit might still be a good thing just in case.

Well, if @joethezombie could please confirm with the seller as per what I wrote in my previous post, that would put my mind more at ease with the purchase.  I really want to know how that Chinese company acquired them and why they still have them after all these years.  It's a valid question since stocking parts that don't sell actually costs money for the storage space.  At the very least, they should be able to supply a photo of multiple chips in their stock.  If the chip looks the same in terms of pins and silkscreen as is shown in my 040 board photo, then it's probably legit.  And in that case, getting them all shipped to you, @Bolle would probably be best for now.  And we can decide payment, splitting, etc. via PM.

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Yes @JDW I'm afraid my Turbo040 is the old one, just as @Bolle says. I won't be able to test whether I have 100% definitely fried my bored for a couple of months but I'm fairly sure I have :/

 

If there's anything I can do to help with Epic Blunders or accelerator stuff though I'm willing to help where I can :)

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@joethezombie

 

Since I don't know the company in China you contacted, I cannot ask them the questions I suggested in my previous posts.  Therefore, if you could please ask them those questions, that would go a long way toward finding out if those so-called "Daystar" VLSI chips are legit or a scam.  Thanks.

 

@james_w Thank you for the clarification that your 040 card uses different chips.

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It was a state-side company, and I have asked for clarification on the authenticity of the chips, and a reimbursement policy.  I'll keep you posted...

 

edit:  Keep in mind, there are also PALs on the newer card as well.  So a replacement of the ASIC may not be enough.  I don't think I'm brave enough to risk my own 040 to test these replacements, either.

But I'll be happy to split the order up and ship them out to whomever wants them.

Edited by joethezombie

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It is only the ASIC that got struck by 12V though.

The GALs should be fine, at least there are no lowered resistances to ground or Vcc on any of their inputs/outputs.

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So I received a somewhat strange reply this afternoon:

Quote

After picking the parts I found that we cannot sell. Parts leads are all damaged to some degree as you can see by photo so we are going to dispose of parts.

 

VY14676-2.thumb.jpg.dab35c542ffe13a49d6801663c1a374a.jpg

 

I have asked if he could dispose of them to me, I'd pay any shipping and handling charges.  No response as of yet.

 

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4 minutes ago, joethezombie said:

So I received a somewhat strange reply this afternoon:

 

I have asked if he could dispose of them to me, I'd pay any shipping and handling charges.  No response as of yet.

 

How bizarre. Lets hope you can get them :)

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Those are all fixable. I’d even pay for them with those bend legs.

 

Edit: chips look legit at least. Mine has the exact same holes on the four corners. Logo and part numbers seem good as well.

Edited by Bolle

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I agree.  I told him that I am a small operation that hand assembles, so fixing the pins would not be an issue.  He probably thinks in terms of an automated setting.

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Telling that particular seller they’re fixable will probably result in him coming back and saying, “After much thought we’ve decided not to dispose of them after all. That will in fact be $100 for the chips.“

 

Even if the pins are fixable, we don’t know how they’ve been handled. If they’ve been zapped with static electricity, well, those pins won’t really matter.

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The chip on my 040 PDS accelerator, which @Bolle currently has, is shown at left in the photo below, while one of the chips Joe is seeking to obtain is shown at right below.  If the top row of silkscreen is a production date code, I would assume my "VLSI" chip was made the 20th week of 1995?  If that's the proper reading, then the "Daystar" branded chips would have been made the 32nd week of 1994.  If true, then it is interesting why the newer chip would have "VLSI" printed on them instead of the Daystar branding.

 

ASICs_Compared.jpg.64077a4f3f3988e07ee42a1d5eaf998f.jpg

 

Regardless, the middle and bottom row of numbers is exactly the same on both chips, so it would appear to be the same revision and should function the same (assuming no damage by static over the last 25 years in storage).

 

 

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21 hours ago, JDW said:

The chip on my 040 PDS accelerator, which @Bolle currently has, is shown at left in the photo below, while one of the chips Joe is seeking to obtain is shown at right below.  If the top row of silkscreen is a production date code, I would assume my "VLSI" chip was made the 20th week of 1995?  If that's the proper reading, then the "Daystar" branded chips would have been made the 32nd week of 1994.  If true, then it is interesting why the newer chip would have "VLSI" printed on them instead of the Daystar branding.

 

 

Doing a quick Google Image search, there are indeed Daystar Turbo040 cards with the "Daystar" labeled ASIC.   And all the ones I looked at had the 1994 date code.

 

I really hope the supplier can be persuaded not to dispose of them, except to us/you.

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You know, it's possible that those chips have bent pins because they were pulled off of failed Turbo 040s when Daystar re-worked warranty covered cards.    And then somehow the tray of pulled chips made it into the sales channel.

 

There are many other possibilities too, others not so depressing, but it is one thing to consider.

 

Although, if the above was the case, I don't think the pins would look quite so clean.

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2 hours ago, trag said:

You know, it's possible that those chips have bent pins because they were pulled off of failed Turbo 040s when Daystar re-worked warranty covered cards.    And then somehow the tray of pulled chips made it into the sales channel.

Meaning, they could be a bad batch as a result?

 

If they really are committed to "disposing" of them it would be completely stupid and moronic for them NOT to ship the chips to Joe for the cost of shipping.

 

Another idea.  If there is a huge number of these chips, would there be a quick and dirty way to test them all?  If there is such a way, perhaps a deal could be struck so that the excess chips which test good could be sent back to the seller so they could sell them as known-good chips, if they like.  The deal could be structured so that Joe (the tester, whoever) gets x-number of the chips free of charge for doing that testing service.  But probably the only way to test them would be to solder them into boards, and that wouldn't be so great for the chips or the board which repeatedly gets soldered and desoldered.

 

Anyway, I am just hoping this works out.  It's an enormous loss if it doesn't.

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