GekkoScience BM1384 Project Development Discussion

[sidehack]

I choose the best of both worlds, and tend to write mean things in long, well-thought-out posts.

I'm hoping for a regulator efficiency such that we can run a Compac stock at 150MHz (8.25GH) off a 500mA 5V port. I also want the Compac to be capable of taking in 1.5A of 5V comfortably. I've only got one powered hub to test with, but it's one I rebuilt with beefed-up 5V lines, a couple extra capacitors and a Molex for power.

Also, I wired one board straight to another board in an effort to cut down on potential wiring issues causing comm noise or clock jitter that might be hosing up my hashes. I'm still getting HW errors (both boards worked flawlessly as single boards), but clocked at 150MHz I should see 16.5GH; cgminer is reporting about 13 and the 3-hour average on Eligius is 12GH. That makes it look like half the shares returned by the second board are hosed. Better than all the shares, which I was seeing previously. Maybe tomorrow I'll work on chaining up and putting two boards in series. I wonder how the level shifters will help knock out any wiring concerns. If I still get moderate cooperation between the chips I'll probably send off for a modified two-chip breakout board when I send off for Compac prototype PCBs to see about improving performance and getting layout ideas for the Amita board and TypeZero.

But right now it's Friday evening and I'm full up on cheeseburgers and taters and about eight glasses of sweet tea so, gonna relax a bit instead.

[philipma1957]

I choose the best of both worlds, and tend to write mean things in long, well-thought-out posts.

I'm hoping for a regulator efficiency such that we can run a Compac stock at 150MHz (8.25GH) off a 500mA 5V port. I also want the Compac to be capable of taking in 1.5A of 5V comfortably. I've only got one powered hub to test with, but it's one I rebuilt with beefed-up 5V lines, a couple extra capacitors and a Molex for power.

Also, I wired one board straight to another board in an effort to cut down on potential wiring issues causing comm noise or clock jitter that might be hosing up my hashes. I'm still getting HW errors (both boards worked flawlessly as single boards), but clocked at 150MHz I should see 16.5GH; cgminer is reporting about 13 and the 3-hour average on Eligius is 12GH. That makes it look like half the shares returned by the second board are hosed. Better than all the shares, which I was seeing previously. Maybe tomorrow I'll work on chaining up and putting two boards in series. I wonder how the level shifters will help knock out any wiring concerns. If I still get moderate cooperation between the chips I'll probably send off for a modified two-chip breakout board when I send off for Compac prototype PCBs to see about improving performance and getting layout ideas for the Amita board and TypeZero.

But right now it's Friday evening and I'm full up on cheeseburgers and taters and about eight glasses of sweet tea so, gonna relax a bit instead.

yeah sweet tea is a real weakness for me..

Good luck over the weekend. oh let me know if the museum usb sticks that i sent came.

[Meech]

Take it EZ sidehack you deserve a break.  Hagw

[sidehack]

Don't worry Meech, I'm currently reclined on the couch, pantsless, book in hand. Doesn't get much more breakful than that on a Friday night.

Novak was just commenting earlier today that Friday afternoons are sorta our weekends. After a full week of work we tend to slack off on Friday afternoons (he took off today about 2PM) and then come Saturday we end up coming back in to work because, hey, we already slacked off on Friday. I spent pretty much all of the post-cheeseburger evening reading webcomics and haven't done anything productive since 4PM. This weekend will be pretty slow for me; with the exception of some basic Amita testing and rough PCB redesign, I have not much minerwork to do until fresh regulator parts arrive Monday.

[Swimmer63]

@phil
We do not have any of those dual chip (NF2) miners, although we do have a couple of the similar six-chip NF6.

I think I have a few NF2s left around - they're considered "defective" as the asics underperformed significantly (and I haven't bother to unsolder them). Aside from that they work sufficiently fine for testing and experiments. If you want PM me your address and I can mail you one.

I also have some poor performers around, including some NF6's.  PM me if you guys need some.

[brush242]

As long as the United States still has people that need jobs, we will never outsource manufacture to a different country.

Could you contact GE & several other large corporations & get them to see things that way 

No, of course not. GE and most of the rest of the other large corporations understand specialization and the division of labour and they know better. They also know why every single thing on earth ISN'T built in Burkina Faso, or wherever the cheapest labour on earth can be found.

Imaginary lines on a map are generally meaningless for making the lives of people better, and adhering to them absent a solid economic foundation just puts upward pressure on costs.

[sidehack]

Profit margins and excessive management wages also put upward pressure on costs. In the last 50 years, adjusting for inflation, the average worker wage in the US has not changed at all while average CEO wage has increased by an order of magnitude. When there's a job that can be done by anyone with basic dexterity, there's no reason to ship your materials twelve time zones away when the guy down the street from you is looking for work. My political leanings have always bent toward isolationist, and the 5:1 trade defecit with China doesn't help convince me I'm wrong. Then again, I also don't like unions - bashing people over the head to get what you want is only required when what you want is undeserved, or when your boss is a jackass, and then there's all the artificial limitations you impose on yourself when you sign away your individual rights to an organization.

So yeah, imaginary lines on a map are generally meaningless. But when I KNOW a guy that doesn't have a job and is about to get kicked out of his house, how @!#$ing dare I hire someone 8000 miles away to do work he could be doing just as well, without communication hassle of time zones, or added transport costs, or supervision costs to maintain basic quality control? How @!#$ing dare I export the economy of the imaginary construct of my country, my state, my county, my town to some hole on the other side of the world just because I want to save a nickel per unit and pocket most of that nickel for myself? Hell no. I'll pay my neighbor to do good work before I'll pay anyone else. If the cost is too high, either I'm paying him more than the job should be worth or, God forbid, I'm paying myself too high a fraction of the revenue I'm not laboring to create. Domestic labor only causes undue pressure on cost when too many of the people involved are greedy.

[philipma1957]

Profit margins and excessive management wages also put upward pressure on costs. In the last 50 years, adjusting for inflation, the average worker wage in the US has not changed at all while average CEO wage has increased by an order of magnitude. When there's a job that can be done by anyone with basic dexterity, there's no reason to ship your materials twelve time zones away when the guy down the street from you is looking for work. My political leanings have always bent toward isolationist, and the 5:1 trade defecit with China doesn't help convince me I'm wrong. Then again, I also don't like unions - bashing people over the head to get what you want is only required when what you want is undeserved, or when your boss is a jackass, and then there's all the artificial limitations you impose on yourself when you sign away your individual rights to an organization.

So yeah, imaginary lines on a map are generally meaningless. But when I KNOW a guy that doesn't have a job and is about to get kicked out of his house, how @!#$ing dare I hire someone 8000 miles away to do work he could be doing just as well, without communication hassle of time zones, or added transport costs, or supervision costs to maintain basic quality control? How @!#$ing dare I export the economy of the imaginary construct of my country, my state, my county, my town to some hole on the other side of the world just because I want to save a nickel per unit and pocket most of that nickel for myself? Hell no. I'll pay my neighbor to do good work before I'll pay anyone else. If the cost is too high, either I'm paying him more than the job should be worth or, God forbid, I'm paying myself too high a fraction of the revenue I'm not laboring to create. Domestic labor only causes undue pressure on cost when too many of the people involved are greedy.

Such a difficult subject protectionism vs free trade.  I won't touch it. But isolationism  that subject Always sparked  my interest. Teddy Roosevelt  wrote on it and his idea was Panama to Canada and all counties in between USA, Mexico , Costa Rica should be a single nation.  Well that never did happen but if it had it would have been close to a perfectly sized and shaped nation to practice isolationism.

As for unions they suck, but not as much as an asshole boss that believes "nothing counts but more"
Pop question the quote "nothing counts but more" is from a sixties pop-rock group .   which one and which song?

So far off topic but the op and I have some similar thoughts.

[sidehack]

Yep. Novak and I share a lot of opinions with grouchy old people, despite being in our twenties. It's pretty fun.

I tend to ask more from people than is normally expected, but I generally only expect between a half and a quarter what I'd expect from myself. There's a lot of the reason I don't answer every stupid question politely, because I figure answering the question once should be enough and anyone wondering should seek the answer first.

The things I despise most about American culture are summed up succinctly as "greed". Laziness is based on greed, a selfish desire to be sedentary at another's expense. Americans love money, but don't really understand the purpose of money. Simply having a lot of money is stupid if that money isn't working for anything. Money is a tool. Money is simply a means of exchange between goods and services, so amassed wealth is actually a detraction - it hurts everything else around you.
America loves cities. Our political, economic and social systems are set up to reward people that congregate in cities at the expense of rural areas. But rural areas are where almost literally all of the actual production happens, where all of the actual resources exist. Cities are huge consumers because the demand curve is shifted heavily by population density, and because the only resources produced in cities are management (which is to say, people charging inordinate sums of money to make decisions about things they never see) and maintenance services (which is to say, the oft-underappreciated toils required to keep management alive and comfortable). Cities are places for stagnant wealth to amass, and for some of that wealth to shift from non-producers to other non-producers, and leave all the producers out to get walked on.

I can't really claim to be a patriot, not like a lot of people I know in military and civil service. Heck I'm not even registered to vote. But one thing I can't stand is businesses leaving the country or jacking up prices so they can increase profit margins. Shifting your central offices to Canada so you can avoid paying US corporate tax? Bastard, you just lost my business. Shifting your manufacturing to China so you can avoid paying a fair wage for a reasonable workload? Thanks but no thanks. Asking your customers to pay you $100 per unit on a thing that only cost you $30 to make - $5 in materials, $5 in assembly labor and $20 in management wages - because you think your ability to wear a necktie and occasionally make selfish decisions earns you the income of ten thousand households a year? Screw that forever.

So yeah, there's good reason for large corporations to specialize, and outsource, and do all kinds of other stuff to protect their bottom lines. But in my mind, a great way to keep costs down is to pay MANAGEMENT a fair wage instead of worrying about making bosses millionaires while profiting from slavery. Find people willing to work hard, with an eye for quality, and let them do it. Then find people willing to stand in front of them (not above, in front) to keep them organized, and pay them about the same amount. And then find someone willing to stand in front of those guys (not above, in front) and keep them organized, and pay them about the same amount. Increasing wages by an order of magnitude with every step up the hierarchy is stupid. If delegation is in any way effective (which is to say, because you hired competent people capable of making decisions and being accountable for them), the workload at any tier of the hierarchy should be about the same as at any other level. Even if Novak and I's concern ever becomes a multi-million-dollar business, we'll probably never get paid a six-figure sum. If you make $1M a year and oversee 100 employees, you could reduce your wages to twice the US median family income (six times what I'm living off now) and still give a $9000 raise to every single employee without increasing costs one whit. Only greed prevents this from being standard practice.

I have pretty stiff opinions about how to do things, and most of them are based around not being a greedy dick. Please don't clutter my project discussion thread (wherein we demonstrate how effective we are at not being greedy dicks) with suggestions that I should ever do (or even endorse) otherwise.

[sidehack]

If by "cannot do" you mean "choose not to do" - probably for reasons of selfishness or complacency - we agree. People are often inspired by stories of exceptional people, not realizing that the majority of those people are ordinary people who chose to do something exceptional and put forth the effort to follow through on that decision. Inspiration is useless unless the inspired choose to act.

[philipma1957]

If by "cannot do" you mean "choose not to do" - probably for reasons of selfishness or complacency - we agree. People are often inspired by stories of exceptional people, not realizing that the majority of those people are ordinary people who chose to do something exceptional and put forth the effort to follow through on that decision. Inspiration is useless unless the inspired choose to act.

AHH free will .  I choose to smoke cigarettes and I choose to stop smoking.

The choosing to do the right thing is easy.  The actual process of enforcing your choice for yourself can be difficult.  Ultimately for me to quit smoking I allowed myself to see the truth the pain of withdrawal symptoms is bearable and will stop.

So pushing yourself to do the right thing may feel a bit painful at first but in the long run it  helps you and in many cases others.

Hiring you neighbor at 2x may cost bucks but in the long run makes good neighbors.

[philipma1957]

We are so far off topic, but It is in a good way.

Here is hoping to a nice bit of 2 chip stick news today.  As for the diff adjustment news is good we are at -3.45% with under 24 blocks to go.

translation is right now 1th = 0.01017 btc a day

in 3 or 4 hours 1th will =       0.01059 btc a day

[AJRGale]

oh, them political discussions in Hardware!  just to add my little bit, i have a bumper sticker on my car that quotes: "Thank the truckers and the farmers for your next meal" i should even add "and your Servicemen"

But enough of that, MOUR P0RN!

[sidehack]

Got some more infornography for you today.

Here's the current two-chip rig, with chips in parallel. This is what's been running since Friday or so. I'm still guessing it's signal integrity causing issues, since with the two boards mounted directly (the shortest possible inter-chip signal path using our breakout boards) the errors dropped from 50% to 25% (based on hashrate efficiency).



And here's some new toys I built today.



The center stick is a test board of the new regulator design. I had trouble with it for a few minutes, but it was just the bootstrap pin not soldered properly. I took it up to about 7.8A without noticeable trouble (I wasn't observing output ripple though, just the average with a multimeter) so I'm already liking it better than the previous design.

The guy on the left is a new USB power meter. I haven't attached the second socket yet, as I was using it for impedance measurements. This guy takes in USB signal+power in the B socket. The currently-headered pair of pins right above the B socket allow for USB power to pass through. If that's not jumpered, the 4 pins adjacent (two +V, two GND) are the power input. The two pins past that (labeled A and G) are the current meter pair; voltage on the A pin (with respect to G, the ground) is approximately 100mV per amp of current. After calibration (linear regression on 12 data points from 50mA to 3A) the actual current is 0.99 the measured value. The second set of pins, by the USB A socket, is for measuring the output voltage at the sockets. The first socket (present) gets USB data, but the second will be power only. I set one up with two sockets because I want my regulator board pulling from USB to emulate actual source impedance conditions, and the signal socket runs the USB-UART adapter (which is also powering the PLL and IO LDOs on the breakout board).

The guy on the right is a stripped-down version of the above, except designed to socket right inbetween my regulator board's output and the BM1384 breakout board. It's only got two pin sets, one for voltage and one for current. A linear regression on its calibration (14 data points between 800mA and 10A) had up to 3% error in the low end (below 4A or so) and I wasn't really happy with it, but for some reason 0.97(Im^1.01) yields between a maximum error of 0.83% with an average error of 0.33% so I'm okay with that.
There's a CR2032 button cell socket on the other side, so this guy is a self-contained meter. Unfortunately with a Vcc of 3.0V, I can only measure up to a bit below 10A, since I'm using a 3mOhm sense resistor, DC gain of 100, and my output is divided by 3 to scale evenly to 100mV/A which means my maximum voltage range at the output pin is 0-1V.

Now that both meters are characterized and calibrated, I can hook them up to the new regulator board tomorrow with an adjustable dummy load and get some efficiency curves. If it behaves how it should, after that I'll tie in a single-chip BM1384 board, the USB-UART adapter and LED circuit and get an actual matrix of Compac W/GH performance data. Expect news tomorrow - hopefully good news, but all I can guarantee is there should be news. And also sandwiches.

If the regulator works how it should, I'll finish redesigning the Compac board and might post some sample layouts. I'll probably also put together a basic two-chip BM1384 breakout with both parallel and string IO/power options so I can better test chip cooperation for Amita and TypeZero designs. As soon as both of those boards are ironed out, we'll be sending off for prototype PCBs. If the Compac board tests well, we'll be looking to ship a few out to our selected testers for finagling. If they report back with favorable reviews, we can start looking into batching a big order.


Also, on a side note, Novak's getting really darn good at toner transfer etches. That regulator chip is a 16-pin 3x3mm QFN package, and the current sense amplifiers on the meter boards are SC70-6, which is about half the size of a SOT23 and twice as many pins.

[philipma1957]

looking forward to a final product. for testing.

[Xian01]

Great work dude ! Love following your progress as usual

[alh]

I agree with Xian01. While I don't completely grok some of the more esoteric electronics, I get enough to follow along. Thanks for the very open discussion of what you are doing.

[elrippo]

Very NICEEE 

[cavaliersrus]

side hack and novak i am really enjoying seeing the updates and seeing the progress is looking very nice and promising cant wait to buy one or a few of these to use and would love to test this out from a novice user's prospective

[sidehack]

I'm working up a one-FET dummy load right now, nothing fancy active control, just a multi-turn pot on the gate. Coupling that with the two power meters (source and load) I'll be able to get efficiency curves for the regulator pretty quickly and I should have some fresh extrapolations for the hashing efficiency later today. And yes, I'll take more electroporn pictures for y'all.

I'll admit, all the time wasted trying to iron out the old regulator circuit was fairly disheartening. But I'm much more confident about this one, partly because it's less complex and more modular - both of which things I really like in a design. I'm starting to wish I'd gone this route to begin with instead of looking for a monolithic solution. It does save quite a bit of space, but at the cost of plenty of suck, apparently. And there are almost no options for going below 0.6V natively in a monolithic buck regulator.