GekkoScience BM1384 Project Development Discussion

[valkir]

Im working in x Ray.  Im a biotechnologie engineer so if you want Send me a pcb I will image it.

Cheer
Valkir

[1714203062]

1714203062

[1714203062]

1714203062

[ZenFr]

The project for a (ultra) low power stickminer is great.

 For example, if BM1384 is 0,3 W per GH, it's can be ~5 W for 15-20 GH :-). USB 2 power supply can go up to 10 W, then the maximum will be 33-40 GH/s, perhaps 50 GH (with higher voltage).
The important thing for personnal use and learning/hobby is that it must be cheap and sold per individualy or in pairs (but not by 500 units ;-)).

Thanks for the job :-).

[quakefiend420]

Any thoughts on programmable fan headers for the TypeZero boards?  PWM fan headers would be neat...I have a few Terraminer IV cases sitting around that could be cool to populate.

[vayvanne]

$9 PC https://www.kickstarter.com/projects/1598272670/chip-the-worlds-first-9-computer?ref=video
why do we still need separate PC with wiring connection as a controller?
is not Bluetooth reliable enough to control mining boards?

[sidehack]

If you're wanting over 20GH from 10W you'll need to wait for the two-chip stick. It should actually hit slightly better efficiency than the one-chip.

The TypeZero will have 4-wire fan headers. How they operate and/or are configured is in Novak's domain right now.

Bluetooth? Not on anything I ever run, which probably means not on anything I ever build. Our boards are USB tethered, so you can hook them to anything you want and run that wirelessly if you feel like. But I'm not going to limit people artificially to "you have to use this type of networking" because nobody wants the same thing. Slap a cheapo USB-enabled controller on it and do whatever you want from there. Sure I know people seem to like having things they can plug in an ignore forever, but building something that you can only plug in and ignore is stupid. Flexibility and configurability are not. That's where the fun comes from, and most of the learning.

[ZenFr]

If you're wanting over 20GH from 10W you'll need to wait for the two-chip stick. It should actually hit slightly better efficiency than the one-chip.

OK :-).
Do you know when the single-chip will be sold, and the dual-chip ?
Even an estimated date ?
Thanks.

[philipma1957]

If you're wanting over 20GH from 10W you'll need to wait for the two-chip stick. It should actually hit slightly better efficiency than the one-chip.

OK :-).
Do you know when the single-chip will be sold, and the dual-chip ?
Even an estimated date ?
Thanks.

No he does not.  As of today he has yet to mail the testing demos to a few of us.

If you want my guess which is worth less.  Here goes.  he mails/ships the tester 1 chip sticks not later then May 21.  We test we like.

So on may 31 he attempts to get a shit ton of chips from bitmaintech.  Since I can not and he can not predict how bitmaintech will be about sending chips.

I will guess the fastest he gets chips is June 14th.

[ZenFr]

No he does not.  As of today he has yet to mail the testing demos to a few of us.

If you want my guess which is worth less.  Here goes.  he mails/ships the tester 1 chip sticks not later then May 21.  We test we like.

So on may 31 he attempts to get a shit ton of chips from bitmaintech.  Since I can not and he can not predict how bitmaintech will be about sending chips.

I will guess the fastest he gets chips is June 14th.

Thank you for this answer :-).

[vs3]

$9 PC https://www.kickstarter.com/projects/1598272670/chip-the-worlds-first-9-computer?ref=video
why do we still need separate PC with wiring connection as a controller?
is not Bluetooth reliable enough to control mining boards?

by the way this is not exactly a "PC" (in terms of what people usually presume - e.g. "IBM PC"-compatible).

Think of it as a stripped-down RaspberryPi 1 (without the HDMI port and SD card) and adding the 2.4GH radio module (for WiFi and BT).

Nonetheless - a great undertaking! I quite like it! And already pre-ordered the kernel kit! Thanks for sharing this!

[Ikron]

I think selling DIY kits would come as a great benefit for newcomers since I personally found that building miners like the nanofuries taught me a lot about soldering and really got me into this bitcoin stuff. Can't wait to see what the product will look like.

[alh]

I think selling DIY kits would come as a great benefit for newcomers since I personally found that building miners like the nanofuries taught me a lot about soldering and really got me into this bitcoin stuff. Can't wait to see what the product will look like.

While I am NOT sidehack, I would be well and truly surprised if he send out a "kit" of parts that need to be soldered in any way shape or form. As I understand it, the BM1384 ASIC is VERY tricky part to get correctly soldered down. Read up on "Ball Grid Array" for more details. I expect your work will be associated with astuff mostly external to what he supplies (USB hub, some kind of PC, etc).

[TheRealSteve]

As I understand it, the BM1384 ASIC is VERY tricky part to get correctly soldered down. Read up on "Ball Grid Array" for more details.

While it is a tricky chip, it's not a BGA - just a custom package akin to a QFN with multiple exposed under pads that are a bit more like an LPCC.  You can check the limited datasheet: https://www.bitmaintech.com/support.htm?pid=00720141220132903742H2RLy6C40630
While there, check out the BM1382 as well - that one would be worse

[sidehack]

If it was BGA I wouldn't be messing with it. The QFN is bad enough by itself. I wish this chip had a larger cross-section of pad at the edge, which would make checking solder jobs better because it'd wrap around a bit. I think the most problem I have right now is being able to stick the chips down reliably. The alignment is difficult because there's basically zero reference for when it's in place (and it has to be correct within a quarter millimeter on two axes) and I can't trust floatation because if there's enough solder on the belly pad to float into place the pins might not get soldered, and if I press it down to connect those the belly solder could bulge out and short across to anything, including the corner Vcore pads and short out basically anything.

I've succeeded in getting two of four sticks hashing unstably and unreliably but I have seen submitted shares. I can't say for sure what the issue is that gets the chip working haphazardly at about 10% capacity, because the breakout boards were pretty much all-or-nothing. Could be signal integrity issues, I really don't know but I hope that's not the case because if it's a result of PCB layout we got problems. The signal traces are between ground planes - at least they should be if the etch fab didn't get layers out of order.

Anyway, here's a sneak peek at the sticks.



Got ya a fully populated boar with heatsink temporarily attached. The final heatsinks will probably be that dimension but anodized green. Note that about 2/3 of the visible area is the bigass regulator, complete with external FETs and 360uF of output capacitance for handling about 20A of low-volt DC. The adjustment pot is in the bottom corner.



Here's some crap plugged into my jankety powered hub. The crapstack in the back you might recognize as a 1384 breakout board on the test regulator and running off one of Novak's USB adapters. The thing in the foreground is literally everything I just said except on one board quite a bit smaller. You might note a lot of flux crust and such around the ASIC. That's because I've pulled the thing, restuck the thing, wicked pads, pushed it around and whatever probably close to a dozen times. Ain't fun when every piece of the circuit seems to work just fine except for the core. Let's think of it as "in a vegetative state".

[ManeBjorn]

You are on a roll.  This project is so cool.  I really look forward to these.

If it was BGA I wouldn't be messing with it. The QFN is bad enough by itself. I wish this chip had a larger cross-section of pad at the edge, which would make checking solder jobs better because it'd wrap around a bit. I think the most problem I have right now is being able to stick the chips down reliably. The alignment is difficult because there's basically zero reference for when it's in place (and it has to be correct within a quarter millimeter on two axes) and I can't trust floatation because if there's enough solder on the belly pad to float into place the pins might not get soldered, and if I press it down to connect those the belly solder could bulge out and short across to anything, including the corner Vcore pads and short out basically anything.

I've succeeded in getting two of four sticks hashing unstably and unreliably but I have seen submitted shares. I can't say for sure what the issue is that gets the chip working haphazardly at about 10% capacity, because the breakout boards were pretty much all-or-nothing. Could be signal integrity issues, I really don't know but I hope that's not the case because if it's a result of PCB layout we got problems. The signal traces are between ground planes - at least they should be if the etch fab didn't get layers out of order.

Anyway, here's a sneak peek at the sticks.



Got ya a fully populated boar with heatsink temporarily attached. The final heatsinks will probably be that dimension but anodized green. Note that about 2/3 of the visible area is the bigass regulator, complete with external FETs and 360uF of output capacitance for handling about 20A of low-volt DC. The adjustment pot is in the bottom corner.



Here's some crap plugged into my jankety powered hub. The crapstack in the back you might recognize as a 1384 breakout board on the test regulator and running off one of Novak's USB adapters. The thing in the foreground is literally everything I just said except on one board quite a bit smaller. You might note a lot of flux crust and such around the ASIC. That's because I've pulled the thing, restuck the thing, wicked pads, pushed it around and whatever probably close to a dozen times. Ain't fun when every piece of the circuit seems to work just fine except for the core. Let's think of it as "in a vegetative state".

[valkir]

This is pure drug to me! Can wait to get these little stick miner 

[sidehack]

If by "on a roll" you mean "several weeks behind ideal projection and frustrated these things didn't work last Thursday", then yes I'm on a roll.

At least the LED works. Some people won't really care if it mines or not so long as the LED works right.

[TheRealSteve]

Only if it blinks

Sounds like progress, regardless.. if nothing else you're probably learning ways to get that chip soldered down more reliably.

[Bicknellski]

If by "on a roll" you mean "several weeks behind ideal projection and frustrated these things didn't work last Thursday", then yes I'm on a roll.

At least the LED works. Some people won't really care if it mines or not so long as the LED works right.

Careful. People might mock you if you have a blinking LED and it mines.

Behind?

If you are the only tree left in the forest...

Carry on. Reflow...

[sidehack]

Yes, behind. I was hoping to be on TypeZero design by now, and I haven't even gotten working Compac prototypes distributed for testing. Just because I'm not racing other independents doesn't mean it's not a race. I'm also racing new chip generations, and the network as a whole, and my own opinions about how long a thing should take to get done.

[Bicknellski]

Yes, behind. I was hoping to be on TypeZero design by now, and I haven't even gotten working Compac prototypes distributed for testing. Just because I'm not racing other independents doesn't mean it's not a race. I'm also racing new chip generations, and the network as a whole, and my own opinions about how long a thing should take to get done.

There is no competition whatsoever. But try as best you can to stick to an internal timeline allow for bloat and miscalculations. You know how design process goes. Tweaking is a major time hole. You are building something that is pretty persnickety especially those tiny pads on those chips. Hand picking and placing is not easy stuff nor is the getting the solder stencil right by hand.