Re: Flash Boards

On Thu, Feb 01, 2007 at 05:28:53PM -0500, Mark Gollahon wrote:
> 
> Not seriously hard, but it is going to be tricky - I will have to write a program
> as well as design the hardware - all while not knowing if I am getting the hardware
> signals right or not (I've not created a flash programmer before).  I've already
> reviewed a number of custom flash programmers that hobbyists have been kind enough
> to post, but none of them are exactly what is needed (most of them are waaaay too
> slow - overnight programming is ok for one-offs, but when you want to do twenty of
> them, well, its not good enough).

Ok, so let's first look at what programming options we have (not in any particular order):

1) JTAG
2) USB
3) the system board connector

1) This would probably be the easiest, however most limited option.

2) This would be quite fancy, and shouldn't be too terribly hard to add. What is the data
   path between the flash board and the system board?  Could we piggy-back the USB bits
   into the system and be able to add a USB host adapter to the 720?  That would be wild.

3) This would be the most complicated as we would need to most likely reverse engineer the
   interface to make it work (#2 makes the a phase II option as the onboard USB would be
   able to be used for flashing) in the first place, so while neat, probably not an option.

> And don't forget someone still has to put together the bootloader that will go into
> the flash....  The only non-x86 bootloader I've had experience with so far is RedBoot,
> and that has been as a user and not a developer.

I keep meaning to start working with RedBoot and eCos.  Maybe this is the perfect opportunity. :)

> Needless to say, there is a lot more work to do than just putting a board together....
> I'm hoping that we can interest some of the really hard-core "gear-head" embedded types
> to help out or take over the bootloader once the board is ready.  They'd probably be able
> to get things running faster than I would.

I'm a software guy, new to the embedded field, but I do know quite a few people who are just
completely freakin' amazing with embedded stuff, so I might be able to dig up some
resources.

>From the very positive response on this list of who wants boards, I think we should be able
to get ourselves into a cheaper quantity discount fairly easily.

-brian
-- 
"The reason I don't use Gnome: every single other window manager I know of is
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