Post
Topic
Board Hardware
Re: [Work in progess] Burnins Avalon Chip to mining board service
by
burnin
on 20/05/2013, 15:47:32 UTC
Hej burnin, could you please post a reply on zefirs post https://bitcointalk.org/index.php?topic=177827.msg2208716#msg2208716 ?

I want to support your project so you can get few developer chips early.

Big thanks to anyone supporting me with their evaluation chips!
I'll also contact Zefir directly.

To anyone that ordered Chips from Zefir, please support me with your evalutions Chips.
Details here:
https://bitcointalk.org/index.php?topic=177827.msg2208716#msg2208716

Hi burnin,
what about the pre-calculation mentioned in the ASIC datasheet (section 4.2)? Isn't their FPGA doing that? Or cgminer does that automatically? I'm not sure how difficult is to compute that for each ASIC when it is doing 300 Mhash. I don't see the nonce mentioned there, so probably only one pre-calc is needed for each chain of 10-20 ASICs?

At the current stage the precalculation will  be handled by the PIC.
If that turns out to be too slow we will change the host interface to full custom.

I'm also working on a firmware build to verify that the timing is working as planned.
I am taking a slightly different approach then Bkkcoin for the chip interface.
The datasheet states >125ns but i don't think we can go arbitrarily longer than that.
The Datasheet needs some clarification on that, and we also need the timing of the Report pins.
Even though i expect them to be close to 125ns.

I would like the option to water cool, mainly to cut down on noise and heat inside the room.
I have come up with a very simple DIY system that should be bullet proof and easy for anyone to make.
However to make it possible the board layout would need to conform to some standard sizes.

The system I propose is an aluminum rectangle tube capped at both ends with a hose fitting welded at each end.
The boards to be held in place with 2 x square u bolts. The welded hose fittings and capping can be done by your local welder.

Most places stock the tube in 6 meter lengths so if boards are say 150 wide you could fit 40 boards on the one heat sink (prob not practical to do that long).  As you can have the tube any length it will be flexible solution.

I guess the feasibility of this idea depends on if on if burnin is willing to have a predetermined distance and size of mounting holes to suit a standard tube/u bolt configuration.

Seems like a very cost effective solution, it is feasible.
I'll put in 4mm mounting holes to support this configuration.
I will also release mechanical drawings soon so you can start designing custom cooling solutions.
Board dimensions:
100x140mm,

mounting hole spacing:

^
I 92mm    <- 134mm ->
v