20/09/2004 16:54:10, freesurf
<
juergen.messerer@freesurf.ch> wrote:
>Now I would like to know if somone has written a requirement of
balloon 3.0?
>
>If not, wouldn't it be a good idea to write one?
you could.. but it's unlikely to be a good use of your time.
The spec for balloon3 looks roughly like:
Rework Balloon2 to support PXA27x, with all the required changes
to memory and power supplies.
Use the space freed up to add new toys, make the board more
manufacturable, while maintaining compatability with Balloon2,
and not losing any features of Balloon2.
(Balloon2 featurelist is: (and probably ought to be on
balloonboard.org somewhere)
-----8<------------------------8<---------------
>Intel Strongarm SA1110, to 206MHz
>Rom, to 32Mbyte (really just trying to be boot rom)
>Ram, to 256MByte
>Nand-flash, to 2GByte, including 16-bit interface variants.
>SmartMedia card, to whatever the limit is today
>Codec (16bit, 44KHz, stereo in & out)
>2W per channel power amp (class D, so efficient)
>3 serial ports (2 at 12V, one at 5V)
>Reset and power control.
>LCD interface (including bias voltage generation)
>LEDs & inputs for debug.
>GPIO connectors for easy attachment of various hardware that
doesn't need full bus speed
>USB two slave ports (to attach to a PC) and 2 host ports (to
attach
peripherals)
>CompactFlash socket
>Power supply takes 6-42V - ideal for automotive use OR...
>Single 5V supply (local supply voltages derived on-board)
>Whole address / data / control bus buffered and sent to docking
connector on back of board.
>10*5.5cm (credit card, extended by 1cm on long side)
>Most functionality available with components only on one side of
the
board (but if you
>do want to put things on the bus, you populate the back of the
board).
The licensing is open hardware - all manufacture data is
available, and you can make
(or have made) and sell as many as you like. However, I am _not_
resleasing the
design files, so that it's difficult to generate thousands of slightly
different variants. The
plan is that Balloon is a component - if you want it to do
something else, then you plug
it in (just like a CPU) to a board of your design - for which
template design files are
available.
This is all trying to make sure that the one version of the board is
made in sufficient
volume to get the costs down as low as possible for small-volume
hackers.
--8<---------------------8<-------------------------
And that's it... the board space is the major constraint. If I end up
designing in something that you don;t want, then don't fit it... If I
end up leaving off something that you do want, then build (or pay
to have built) a plug-in board with that function on it. If you
choose, release the design as a favour to others.
The spec is a pile of compromises, and, until it's (nearly) finished,
I'd rather not make any firm commitments. If you've got requests,
now is definitely the time to mention them. No guarantees, but if
you don't ask, then I won't know that you want something...
>What are the goals of balloon 3.0?
>- low power?
>- compact?
>- easy to build?
>- cheep to built?
All of the above. they're not mutually exclusive. (Well, except the
compact and easy to build terms).
Balloon3 is only expected to be easy to build _compared to
Balloon2_. It's never going to be something to be hand soldered -
the BGA packages rule that out - I just want to reduce the
assembly cost.
>Some mention in the list that it would be a good idea to nake
modular board.
>E.g.
>- We could make a seperate board with the graphic chip
2700G.
>- Or a peripheral board with different interfaces
Sure - feel free. I'd be delighted if you (or anyone else) made
boards to suit whatever purpose you fancy. I'll help where I can
(but I'm unlikely to respond quickly to requests to design boards
that aren't generally useful / open sourced, unless bribed).
>- Extendable memory (RAM/FLASH) like on PC mainboards
Very tricky. The sockets take up a vast amount of space, which is
something that is in short supply. There's nothing to stop you
fittingmore ROM on the expansion bus - in either NAND or NOR
formats, or attaching an IDE interface. You can also fit SD, MMIC,
CF or USB drives, or fit a CF network card and net-mount as much
storage as you like.
Adding RAM is tricky. Balloon3 is likely to move to RAM in BGA
packages, which rules out the 4-deep stacking of chips which
Balloon2 allowed (but which nobody used).
If anyone knows where to get low-power SDRAm in TSOP
packages, that would be useful information - I really would rather
not use BGAs for the RAM. It's faintly possible that I could lay out
for both, but I suspect it'd be tricky.
>Can anyone give me a brief statement about the project. Where
we are today?
Today, Balloon2.05 exists, is proven, and ready to go, either build
it yourself, or buy a built one.
Balloon3 is coming, with prototypes planned by the end of the
year. I hope to have the design finalised before that. However, I'm
not burdened with spare time right now.
>I would really like to help.
Cheers. Balloon3 is coming along Ok - if you want to start
developing motherboards to plug it (and, therefore, balloon2
boards) into, that'd definitely be fair game.
Steve
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