Latest update for peer review:

https://www.dropbox.com/s/dstypt5mqgeiz5y/DIY_AVALON.sch.0.3.pdf?v=0swn

Please let me know what you guys think.

There might be a thing or two more I would like to nitpick, but this is pretty close to final.

Thanks

Found a name I really like.

I want to call this thing "The Quarter Stick"

With the release of Avalon spec's and the engineering advancements from
BKKcoins on the Klondike, the design is nearing completion. The Quarter Stick
and the Klondike are very similar other than the number of chips and a few
goodies to support maximum current draw from the USB port and possibly
support external power as well for those that want to push the chip to the
max.

Anyways, between job and family, this hasn't moved as fast as anyone would like
including myself. There's still a ton of emails I never answered.....sorry.
Please try again if you like.

To help speed thinks up, I need an Eagle PCB designer. Someone that can help
speed up layout. Please shoot me an email if you could make it happen in the
next few days.

I need just a few more days to critique the design, update Bill of Materials, and
have it peer reviewed then it is off to designing the PCB. With the right help, it
could be done a few days to a week.

Next PCB design, I'm going with KICAD. Don't know how hard it will be to make it
work, but its open source.

The design challenge is sampling the REPROT_P/N with the PIC. You need to be able to execute 2 instructions on the PIC16 architecture (one for sampling and the other for storing).
This will take a total of: 2 instructions * 4 Clock Cycles / 48MHz = 167 nS.

I think the CPLD is a good idea for the KLONDIKE; I even found some for a dollar; however, for the single Avalon mining device, "The Avalon Quarter Stick", it isn't a pretty solution.
I'm going to try to use the Programmable logic on this controller to smooth out the signal some:
http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en552961
We can use the SR latch to merge the two signals into one and double the amount of time for sampling.
The results: 167nS sampling rate for a 250nS+ signal.

Do you think this is possible? If not, CPLD looks like the best solution.

Whoops..... Wrong pins. I meant to refer to the report pins.

Thanks for pointing out that the spec's are available.
That is awesome!!

I reviewed the clock divider portion and we should be able to achieve the desired hash rate with a 16MHz clock;
so, we can get rid of the clock using the chip you selected.

The way data is entered, I'm sure speed is not a concern. it can be transmitted slower so that is not a problem.

The only concern I have (I'll continue to dig through this spec sheet to resolve it if possible) is the CONFIG_PO and
CONFIG_NO pins. I cannot figure out what are the data rates on these pins and if it can be configured or how the clock is even determined.
I'm speculating that is a 250nS period like you pointed out. If that is the case, It's probably too fast to capture the data
with chosen PIC. I will continue to look into it.

Thanks for checking it out.
What was your rationale behind the PIC selection?

At the time, there was no information on my end about how to interface with Avalon and the chip I selected had a lot of capabilities
when it comes to outputting a clock at different frequencies. Thought it might be necessary.

I was surprised when I saw on the schematic that they are feeding in a fixed clock. That means they must have the ability to adjust the
clock inside the AVALON ASIC for over/under clocking purposes.

Anyways, do you know what speed the data lines use? I was expecting a separate clock for the data, but there is none according to the
labels. This is my last concern before making a PCB. If data is expected to be around 32MHZ, we may have to consider a different micro
controller altogether. Hope Avalon releases more information about this soon.

I'm seriously considering the same PIC selection you made. It's too bad we can't double the internal frequency and output it on a pin
with that PIC; we wouldn't need an external oscillator at all. That is one of the first 8 bit PICs that has auto calibration for a tight clock
frequencies to meet USB spec's.

What do you think of the DCDC setup? There's a MOSFET transistor to isolate the USB port from too much capacitance and inrush current.
the transistor will need to be pulsed a few times initially to get the caps charged without drawing too much current. A large current spike
from a USB port can cause it to auto disable.

I also included an input inductor (after the MOSFET transistor) to lower the current ripple. It will make the miner go a lot easier
on the output circuity of the USB port. Given that this is going to run 24/7, it could put some serious abuse on a computer's USB port that is
very cheaply made. I know it adds a little bit more costs, but I think it will be worth it.

Thoughts?

BTW, I propose we give this the name "Quarter Stick". It will run about a "quarter" of a giga hash and it will cost about a "quarter" of 100 dollars.

Hey,

https://www.dropbox.com/s/j0hkkl4vs9nfx39/DIY_AVALON.sch.0.2.pdf

Here's the updated schematic I have so far. I started in Eagle so it is not compatible with BKKcoins, but my next project i will make it happen in KICAD.

Please take a look. All feedback may help avoid a second revision which is always nice.

Update BOM coming in the next day or so.

BKKCoins,
     Hope you find something useful here. Let me know.

I'm just looking into KiCad for the first time. Very interesting. Has your experience been positive?
This single chip USB miner is what I had set out to do originally (been very busy and away for a while), but still 100%
committed. Most of the non-avalon portion of the schematic is complete with good and cheap components selected ready to order.
If you plan to make this single AVALON USB miner open source like the Klondike, would you post it on Github?
I'll start learning KiCad right away (it's open source; it deserves the time) and integrate my discoveries/designs into
what you have so far for peer review.

Please email me.

BTW, does anyone have a name for this device yet? It needs one.

Thanks for the feedback. You are right. that part is much better for the single avalon chip application.
I don't know how low the ripple current should be. I've looked through all the USB spec's and I couldn't find
anything that addressed this directly. The closes thing I found was related to the initial inrush current:
Maximum = 100mA/1uS

You are probably right.
Looks like I'll have to be patient.  Can't wait though.
Thanks again!

So, could we get this post transformed into a BIP with a strategy for implementation?
If I understand correctly, Gavin has already laid the ground work for changes such as
these to be integrated into the Bitcoin protocol.

Thanks to the OP for getting this out there.

I really like this..... a lot!
This is how I assumed it worked before getting into hardware development, but what a nasty surprise.

Does anyone else see any downsides? Other than it would have to be rushed to fit it in with this planned hard fork.

Really need some core developers to come out in full support of this right away.

OK, I have a preliminary Schematic for engineering discussion.
https://www.dropbox.com/s/9c51uivncr5hhnp/DIY_AVALON_Rough_Draft1.sch.pdf

https://www.dropbox.com/s/ypqbam0uxwtcav9/BOM_Rough_Draft1.xls

Please take the engineering with a grain of salt. I would love to have some EE's look it over and
offer suggestions for improvement. I'm still having difficulty solving the math to yield values for
the following components:
C2?
C3?
R4?
C6?
c7?
L2?

Any help would be appreciated.

thanks,
     Allten

Thanks for the USB reference. Need to download that spec and archive it for easy use.
The closest thing I can find regarding the information I'm looking for is on page 176 (Pg 204 of the PDF).

Says maximum is 100mA/us, but that is for initial inrush current. Maybe I'll use that as a guide.
I was hoping for a spec' that defined the maximum ripple current (maximum current slew rate was probably
not the best way to define that). I'm trying to find a cheap, yet appropriate LC circuit to have on the input of
the DC-DC converter. If there were some numbers available, it would sure make it easier to calculate
instead of just guesstimating what appropriate values should be. I'm sure there is another angle to look at this.
Any help would be appreciated.

Note The converter is built for 2A output max.
The average input current: 2A(1.2V/5V)

Sorry for no updates or responses to emails and posts.
I'll still get to it.....someday.

Been busy trying to get a much better preliminary design together
for a more serious engineering discussion.

Need Help: Can anyone find the specification for the maximum current slew rate on
the USB power signal? I've been looking, but no luck.

Thanks.

Welcome back Zhou.

Look forward to seeing your contributions.

I will raise hell though if you are ever in a position of receiving funds.
But then again, I'm sure you know better and are or would be using another
name and invented identity to run a "bitcon" business

Good Luck! I really do hope the best for you. I'll give you a second chance on
everything except trust.

Low Cost DIY ASIC Miner

Purpose:
This thread is intended for the development of a very low cost DIY open source
ASIC miner based on Avalon's chips. Hopefully, it will inspire other Bitcoin ASIC
manufactures to offer their chips as well.

Objectives:
* Get ASICs in the hands of the masses ASAP.

* Create the cheapest solution possible. The lowest possible price is the goal.
The $ per hash ratio is not expected to be the best.

* Make it simple enough that anyone with a DIY spirit can assemble one of these with
some simple low priced tools.
https://www.sparkfun.com/tutorials/category/2
DIY manufacturing may be an avenue to get these out much faster.
Expect a few hours assembly time per board.

*Make the PCB design that is not only DIY friendly, but mass production friendly as well.
It will use surface mount technology.

*Inspire more ASIC Bitcoin Mining manufactures to pop up all over the world (Decentralization).
ASIC manufacturing in general is the most complicated production process in the world.
IMO, the best thing for Bitcoin would be for ASIC Bitcoin Manufactures to be decoupled from
final product production; or at least offer their chips as well on top of their final products.

Specifications (subject to change):
* USB power source is all that is required.
* Utilizes a single Avalon ASIC
* 256+ MH/s
* 2 Watt maximum power usage
* TYPE A USB Male option on either side of the PCB
* Type B USB Female option
* More to come

Sponsors:
*Burnin - He is a serious manufacture of Bitcoin mining equipment. He has committed to helping
with the open source software/firmware to make this project function. He has started an official
thread for his miners and it's worth checking out:
https://bitcointalk.org/index.php?topic=179769.0

*Zefir - He is preordaining Avalon ASICs in smaller quantities for anyone interested:
funds: https://bitcointalk.org/index.php?topic=177827.0
Zefir is committed to helping this low cost DIY project be successful by making a small quantity
of chips available for ordering and development.

Team:
All of you! An open source design also means its open to anyone. Feel free to take the initiative
to help out in your own way. Please don't get discouraged as it may take time to figure
out where your talents fit in best. I have received an overwhelming quantity of supportive emails
and also many request to help out. I wasn't prepared for that, but now, I would like to make
a list of anyone that wants to get involved here and what they would like to bring to the table.
Shoot me ANOTHER email and I will add you name here.

"Someone42" who was the inspiration and pioneer in hardware wallets has offered his help here.
"Burnin" has also offered his help, but is also very busy as he is preparing his own miner.

Allten's Commitment:
I will engineer the schematic and the PCB. As soon as the chip specifications are available, I will
release within a week a preliminary design for feedback. I will personally manufacture enough
of these to get them in the hands of all those that will be helping with firmware/software development.
After that, a detailed tutorial will be made on how to order and produce these by yourself.

Important note: I do not want to become a distributor for these for the simple fact I would like
to have time available for other projects I'm passionate about. This is a golden opportunity for anyone
or a few people to become distributors of DIY kits and already assembled miners. I will assist anyone
to get set up for this once I've completed the tutorial.

Funding:
Sending some coins would be very helpful and greatly appreciated.
1AqEzSiw7aqZ7T53XvXMqrcnUD5tKcvJxP
What will donations cover? Enough to order the parts and PCBs for the initial boards used for development.
All extra will be used to drive bounties for software/firmware development.
I get the feeling that many have ordered chips with confidence that there will be a PCB solution
readily available before the ASICs arrive. If that is the case, consider donating up to 5% of
what you invested in chips to this project. It would sure help hurry it a long! Much of the bounty portion
may go to "burnin" as his code development for the controller portion will be shared with this project and
he is most heavily invested to make it work along with his product ASAP.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ OLD - For Reference ~~~~~~~~~~~~~~~~~

Update: April 15th 2013

A huge thank you to Avalon for making their chips available. This is a great step in the
right direction for Bitcoin! Hopefully ASICMiner, BFL, and future ASIC manufactures will
follow their lead someday.

Looks like we will still be waiting a little bit longer for some more detailed spec's, but
thanks to Burnin's help, he has shown me that the design is adequate so I'm going
forward with a BOM (Bill of Materials) and a preliminary schematic for everyone's
review.

Here's the BOM:
https://www.dropbox.com/s/45698vk7bpvbdkp/BOM.xls


Update: April 3rd 2013



Update: April 1st 2013

Project is at a stand still until more details are released regarding
AVALON ASICs. I was hoping to encourage BitSyncom to just
give us a few preliminary details in the forum so we could make
sure the hardware design was appropriate. Unfortunately,
That has not happened.

Instead of waiting until complete and official Spec's are available
online I would like to ask anyone with an AVALON that has skills
with an oscilloscope and ohm meter to please help with this.
Shouldn't take too long.

I wanted to offer a bounty, but then I remembered anyone with
an Avalon probably wouldn't be motivated for anything less than
a Bitcoin.

Here are the spec's available so far:
https://en.bitcoin.it/wiki/Avalon#Chip_Specification


What is needed?

1) Pin out for all 48 pins. What pins are ground? What Pins are power? Clock pins? Data pins? etc.

2) Do the ASICs have a frequency multiplier? What is the frequency on the core clock pin? Internal
    core clocked is spec'ed around 256 MHZ

3) What is the data bandwidth on the clock/data lines? Just need to know what the clock
    frequency is for the clock pins and that would be sufficient.

Bonus: are there any serial communication protocols being used: SPI, I2C, Proprietary, etc.?

Thanks!

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Building a DIY Open Source ASIC PCB based on AVALON ASICs

Time is of the essence [obviously] and hoping there will be
a lot of talent that can help make this happen with respect to Firmware
and software. So far its just me with one other who has expressed
interest in an email.

The design is kept as simple and cheap as possible and components were
selected that would be easy to solder. The only difficult soldering
task would be the ASIC themselves and would require oven reflow
(or a skillet). People could get the ASICs pre soldered by someone else
if they don't feel comfortable giving it a try. There will be a tutorial on how
to do a seemingly challenging ASIC soldering job with few tools for those willing to try.

Why do this?

"MiniMiner would be great, and an excellent way to introduce new people to Bitcoin. 
A low cost device with a nice, simple, user interface could really broaden the market. 
I think there's something about mining that really gets people hooked and interested
in learning more." - Anonymous

Also, it was a tragedy (even though inevitable and necessary) IMO when custom
hardware started to come forth. In the GPU and CPU phase where anyone could learn
about it and be mining at the end of the day was a unique period that hooked many
into Bitcoin. I would like to help lower entry to competitive mining with this project.

Why Avalon?
I was inspired by the article about Yifu.
http://motherboard.vice.com/blog/engineering-the-bitcoin-gold-rush-an-interview-with-yifu-guo-creator-of-the-first-asic-based-miner
They are the only ones I trust to be supportive of a project like this. Even with BFL
rolling out their hardware soon and a 28nm ASIC to hit the market later this year,
this is still essential and could pave the way for other ASIC manufactures to consider
releasing their ASIC interface designs and sell just the chips.

I'm much more of a hardware guy and have not been involved at all with any Bitcoin
mining hardware before so I do not know if the design is appropriate.
Please chime in and help me see what's missing and what needs changed.
A schematic will be available in a day or two depending on the feedback received.
I'm hoping the Avalon team will take a moment and give their feedback as well.

Here's the chip Specification that I have found so far:
https://en.bitcoin.it/wiki/Avalon#Chip_Specification

My two biggest design hurdles at the moment:
1)Frequency driver for the Avalon ASIC. What is the input frequency?
I assume it has a clock multiplier, but if not I will need to reconsider that portion of
the design.

2) Having no idea how work is passed to the chip, would 8 data lines with a frequency
of 48 MHz cause a bottleneck? If so, by how much?

Here's a diagram for inspiration. It will give an idea to everyone (technical and non-technical) of what I'm thinking:

I did this with the Bitsafe and the results were very good. I was pleasantly surprised with the method.
Although, I didn't have any QFN packages.

I understand your concerns and there will be no PCB ordered until there is an official Spec'.
Someone with FPGA experience gave me some input that made me feel more confident, but we'll
see. Doing something was better than waiting.