Topic: GekkoScience BM1384 Project Development Discussion - page 67. (Read 146729 times)

Nice!

So, I think I found the problems with the Compac as designed. The ground noise issue was pretty well solved by tying the SGND and PGND together at the ASIC, which neutralized the potentials between local grounds for the VCore and 0.9/1.8V logic power. I also noticed some issues with the regulator occasionally dropping out during startup of the device, because chip init can draw a heft burst current (as noted in previous tests). The output capacitance on the buck was being overwhelmed and tripping out the regulator. I solved that by adding output capacitance in the form of a 470uF tantalum scavenged from a dead Habanero. Which, if anyone's ever stolen parts from a dead Habanero you know that whole PCB is one giant friggin' heatsink. Seriously those things are stout. But with the added output capacitance I was able to start the stick at 650mV all the way up to 250MHz (13.75GH) without issue.

I think the reduced output ripple also caused the ASIC to run more stable, because power consumption was down a bit overall.

Right now the stick is hashing away at 610mV 150MHz (8.25GH) drawing right around 520mA off my test hub. That's 0.32W/GH, not too shabby.

The burst output issue will probably be resolved when we have working dedicated drivers. The S5 code ramps the chips up pretty slowly and I don't see that burst on init like we see with the U3 driver. Hopefully we have working code by the time an Amita is released for testing, since there's no way to test it without working code now is there?

Anyway, so now I have about a dozen PCBs that can be modified to work as a single-chip stick miner. I'm thinking of sending some to my first-wave testers even though it won't be the final product (and probably a homemade heatsink approximating the final) so they can at least start playing with it. I'll be working over the PCB design, checking over the 18-board design, and probably sending off both to fab tomorrow. Once the PCBs for the Compac return and test functional, I can send off for Amita PCBs also since it's an extension of the same design. Boy I sure wish I'd had these errors fixed a couple weeks ago.

The final design will have a different UART level shifter setup, a slightly changed regulator layout (to accomodate the changes in input and output capacitance) and probably a different potentiometer because I don't really trust the one I got right now. If you're playing rough with it and the wiper gets disconnected from the contact surface you'll sorta feed the ASIC with 2V instead of the <0.8V you were going for. I tend to adjust the pot with the Compac unplugged and using a multimeter to set it (which requires the formula for voltage based on pot resistance). I'll probably change the design up a bit to make that fault safer, but probably also spec a new pot anyway.

I have had a lot of block eruptors in the hundreds very few failed. My 100gh r-boxes all worked well. 

Do you have power supply issues?
Do you overclock?
Did you fan cool the usb sticks?

Oh, Mr Sidehack, with your usb miner design, you're using the CP2102 yes? do you have esd/power spike protection on the data lines from the USB to the chip? (i think some smd capacitors from each data line to earth should do it i have to double check the data sheet)

just a thought, since I've has nothing but bad luck with things that run from CP2102s (hand full of usb block eruptors, a zues miner, my "new R-box's" all with fried Silabs chips)

txid: a6aa5090c91753c0b5162bf9aa607868ee272125844a49a253a5e44e30962e0b

Take a beer with that! 

Thanks, guys. So my "days off" turned into a 23-hour excursion with about 9 hours on the road, two hours walking around a stupid city, three hours at a concert, seven hours sleeping and two hours (instead of two days) visiting friends I hadn't seen much in a few years. Not a complete disaster, but certainly a fraction of the intended entertainment.

Maybe that's an indicator that I'm supposed to be at work doing awesome stuff instead of farting around the state.

YEah!  

You can still buy one even if the campaing is over!

Sidehack and Novak 20$ on the way at burger address!

my sidehack Tee-Shirt  has been printed will ship soon.

Guys please use private message! 

i would love to get my hands on another s5 if the price is right..
i have one s5 now, so even if i got another s5 with 1 or 2 semi working blades i can run them off the working s5?

How many S5's did/do you have in total?
Not talking just about broken units.

I'll know later today the number of dead units I have.  I know for a fact that I have one that will light up when powered but won't be accessible over the LAN at all, and I have 4 other units that are flaky (coming online for a varying amount of time then disappearing again, some with X's, some without). 

If that all holds true:

I can send one direct to you, and you can donate whatever funds you feel appropriate directly to sidehack, either the 1BURGER fund, or an address he supplies for development costs.  No need to double-ship, nor a need to have any middle man with the funds.


I can send one or more to you to strip down as needed for parts and/or attempt to assemble one+ good ones to hash at your donation choice.

Either way these units no longer owe me anything, they achieved positive ROI a while back and are no longer under any sort of possible warranty, so I have no issue with tossing them to a better cause.

If he'd rather sell it to you and do whatever with the proceeds, that's on him.
If I couldn't get it working pretty readily I'd strip it for parts, might use chips for prototyping or something or have a second working controller for Novak to play with and have the chassis to stick boards on when/if we have some later.

Id be happy to buy the dead S5 directly, and he can simply donate that to you? It would save shipping it twice to get it to Toronto, Canada

Well maybe others will follow in his footsteps.

I also gave burger money and I am looking forward to my size 2x tee shirt .

Frankly the industry has changed so much in 3 years I am looking at running a node and doing just a little bit of mining.

 Nothing else.
 I would like 3 or four sticks to run with the same gear that runs the node.

Then why post and say you're donating?  Just donate, the post isn't necessary.

nice shirt and before anyone goes donate i did i may even buy a shirt for the hell of it . will donate to the burger found next month i can again then. I want nothing in return and wont ask for anything  you don't even know its me donating i want it that way .

Sure. Maybe if I get another whole unit working I can auction it off for dev funds. I've been considering doing that with some New R-Box units we have laying around. Once I get some Compac prototypes working and the first set delivered for testing, I might have four or five more I could auction off as well. That'd be interesting.

I've got one more dead S5, possibly 2 if you want them (have to see if the second one will power up or not).  If I get time I could ship Wednesday, otherwise early next week, just let me know.

Then buy a T-Shirt or donate to the 1BURGER address