[chbot] FPGAs again

[Charles Manning]

On Fri, Jul 22, 2011 at 9:40 PM, Volker Kuhlmann
<list0570 at paradise.net.nz> wrote:
> On Fri 22 Jul 2011 15:37:01 NZST +1200, Charles Manning wrote:
>
>> I believe the last discussion on FPGAs was silenced by the Feb earthquakes.
>
> :-(
>
>> The choice is really between:
>> * Cheapest: $49
>> * Pay a bit more but get much more toys (DE0-nano): $39.
>
> So the choice is between cheapest and really cheapest... :-))

Sorry, my typo. $79, not $39.

>
> I would be interested. The potential to run Linux sounds good.
> But I don't remember the story about development tools. Do they run *on*
> Linux too? There appears to be nothing mentioning Linux on terasic's
> site, although Altera seems to have at least heard of it and has
> software for it, but I am unsure as to the extent of this and what all
> those names on te Altera site mean.
>
> Did anyone have a look at Linux as development platform, and what was
> the result?


The De0-nano development is done with the Altera tools. There are
Linux versions of the FPGA and NIOS IDE. I therefore assume it is
possible to do everything under Linux.
https://www.altera.com/download/software/quartus-ii-we
https://www.altera.com/download/software/nios-ii


The Terassic tutorial is Winpoo based, but I expect the workflow is
pretty much the same. The Terassic media includes a Windows program
that communicates with the demo images. That might not work, but
that's not really part of the learning.

Other stuff I have found out:
* The DE0-nano board has the equivalent of an Altera BitBlaster (or
whatever it is called) USB  cable built in. This downloads the images
as well as providing a debugging link (think JTAG cable) for software
debugging etc. It can also be used as a target<-->host link for comms.

* There are over 70 FPGA pins that come out on the headers. These are 3V3.

There are various projects that provide Linux running on NIOS2. At the
low end there's a uclinux that runs on nios configured without an MMU
or full-fat Linux running on nios with an MMU.

There are also various RTOS ports to nios too.

Since the FPGA has 22K logic elements and the nios can be configured
as low as 700 logic elements, there's a whole pile of space to do
interesting logic or multi-core dabbling.

Shipping for the Terassic board is approx USD40 based on 3 boards, so
budget USD10 each. ie a total of USD89.

Personally I think that's a bargain for what you get.

I would like to place an order at the end of next week, so please let
me know if you're in.

-- Charles