Topic: Klondike - 16 chip ASIC Open Source Board - Preliminary - page 5. (Read 435369 times)

Correct. Short on a 3.3V rail to the GND.


I've been reworking Avalons on the first few K16, so I have a practice . The issue here is, that it can really be any component, from a capacitor to Avalons itself. Another thing is, that I was in a work from 1PM till now (11PM), so I'm not in a state to start working on that now. I'm sorry, but I'll try tomorrow morning. But as it looks, it won't be probably fixed before weekend .

Zipiju,

That thar is some nice looking PCB work.  Just to be clear, those are Gen2, 55nm Avalon chips AND you're chasing down a short somewhere .... right???  Solder bridge shorts are a true PITA to work out.  On replacing the Avalon chips, I've done tight package replacements using just a hardware store heat gun (on high).  I made an aluminum foil shield to cover the components around the BGP package device I was replacing (so as not to melt their solder) and then ever so gingerly heated the part I needed to replace to a point where it would release from the board using my chip suction device.  It's not quite a hot air re-flow station BUT it does the trick.  To replace the part I tinned the pads on the PCB, put the part on the board, held it in place with a long rigid wire (because I didn't want to toast my fingers in the process) and again used the heat gun to re-flow the tinned pads.  If don't want to pre-tin the pads and you happen to have solder paste laying around you can dab a small amount (and I mean a pin head amount) onto the device pads and then, using your chip suction device, line the device up with the PCB pads and drop it onto the board.  The heat gun process applies once the part is stuck to the board.  On a final note, I always part with a bit of advice.  Do NOT drop that hot heat gun on your junk   .  In fact, try to NEVER do electronics work wearing only a Speedo.  Safety first  

On the topic of solder bridges that can happen with REALLY tight pitched electronics used on the K16S-55nm board have you considered building yourself one of these -> http://www.instructables.com/id/DIY-Soldering-Reflow-Oven/ .

I did and it makes doing tight pitch packages as ell as BGM type packages SUPER easy (using a stencil and solder paste).

H@shKraker

Nice looking pcb :-) hope you can find the problem m8 

And peeps keep this thread related to the open source project please

Those are Gen2, but Avalon made a mistake with that batch, so they are marked as A256. I was told that by the guys from the Avalon when they were sending them to me.

It's really low, like 14 Ohms.
I'll be working on that later today. But it seems, that I will have to remove all components that are using 3.3V rail, one by one, because no visible bridge is there.

EDIT:
Maybe that burned 3.3V reg just punched through one of the ASICs, or NOR or something.

zipiju I sure hope you can find that short with a visual inspection.
Otherwise it's going to suck.
How low of resistance is the short?

Gen1 is different pin map from Gen2.
for example,
pin number #20
A3255-Q48(DVDD)
A3256-Q48(DVSS)

no the chips have the same packaging and marking except for like 1 number

It seems to me that the first generation chip(avalon).
Is right?

can we has a pic?

Guys, just an update.
I've assembled K16s v1.0. As a precaution, I've measured conductivity between powerrails and grounds as usuall, but unfortunatelly, 3.3V reg burned out anyways .
It was working for a while, so solder bridge probably caused that (it happened to me before).
I've replaced it, but now the 3.3V rail is shorted to the ground somewhere, so I'm debugging that now.
I've tripple checked the schematics and the datasheets today, and it's 100% correct, so this is really just an issue with solder bridges.
I just hope that the short is not beacuse of burned out ASIC, beacuse replacing those it's pain in the a**.
As soon as I'll have something new, I'll post it ASAP.

Someone designing open source money printing machines should probably see that coming, not that it was truly open source with the psuedo-DRM firmware bkk wanted to have so he could get paid.

I think the thread is Zipiju's actually seeing as he has taken the lead. Seems like he just wants to pass along information to everyone and that seems like the right thing to do. Your call do what you like the thread to be I have already said my piece regarding smearing the reputation of someone without evidence and the reasoning behind it. Let us hope we see people get their "Klondikes" running and mining and as I said before  that I hope BKKCoins can do whatever he can to pay people back. If anyone starts a new thread to throw some coins together to help offset his burden and pay others back then let me know. I will leave those interested in what Zipiju is doing to do just that and stop posting further. Good luck.

Why, because you want this to be your thread now? IMO the fate of the Original Poster BkkCoins is still on topic in this thread. HIS thread.

Besides, THIS is the thread people will know to come back to if they want to check the status of possible refunds. Why? Because they ordered products based on the discussion in THIS thread.  Not some other new one buried out there in the forums.

I do agree that repeated bashing of BkkCoins is not warranted, and is just boring.

Having to catch up on this topic (as I didn't follow it from the beginning) yes, I wished it had only technical information (not crap about heatsink). Now that I am sort of following it, some drama details are always welcome  .  And, who the hell would read that other thread?

Anyway, my point was that BKK made a good impression from the start. People who lost money should not just blame BKK, but also those scumbags who made posts like "can't wait to start selling these".

My take.

All this speculation is deserved in another thread on that specific topic.

------

Zipiju and others have gracefully taken up the work BKKCoins left and that is what the topic should be about now.

Can we agree about that?

Here is my opinion for what it's worth. I think that accident didn't happen and he ran away with the money. However, I think he deserves that money   (I didn't order anything from him by the way so it's easy for me to say). I am actually surprised he put so much work for so little amount of donations, and not sure why he didn't run away earlier seeing how some scum of the earth were openly planning to profiteer from his work. Although, majority of those who ordered from him were decent people in my opinion and I am sorry for their loss.

Oh, thanks. I had already seen that post. From the way h@shKraker was talking he was practically a vegetable, and I wondered when that had happened. After all, in the post  you mention he says "I am ok physically now."

I obviously can't say if his accident was real or not. I tend to believe him. Assuming it's real, that post sounds like a guy who's had a terrible accident, but is likely to have a full recovery.

Perhaps at this point BkkCoins is simply struggling to make ends meet and put food on the table after experiencing a grave financial setback. Whatever his situation, he's healthy enough to have at least posted here a few times since the alleged accident. Given that, I'd think the LEAST he could do is cut and paste a message/update of some sort to all the folks he owes money to (I'm talking direct communication, not a blanket post in a forum thread). I'll bet if the explained the situation, a lot of people would give him the benefit of the doubt. As I've already stated, I'm prepared to not hold him to what he owes me. But I'd still like a response from him!

Taking the other view, it IS plausible that the accident didn't happen. BkkCoins was obviously under a lot of stress right before his disappearance. Yifu's fuck up had hit us all pretty hard - we KNOW that was a huge blow to BkkCoins. He'd also had the sample chips for a few days. He'd likely had time to realize the K16 as designed had significant issues. Those issues may have been more than he was willing to face at the time, and he decided to bail. I don't think that's what happened. But IMO we need to face the fact that it IS a possibility.

Well said :-)