>>> 2) access to PCB manufacturing
>>> 10 pieces of a 4-layer PCB cost ~$1200 and need 4 weeks
>>> for processing.
>
> I have access to simple two-sided PCB manufacturing facilities.
> PCB layout on the other hand is hard to come by...
The PCB layout is no problem. I know someone who can do it with Orcad.
>>> Current dream: a big FPGA connected to ALL the ISA pins, programmable
>>> on the fly by the PC itself; a fast 32-bit micro with very fast comm
>>> ports (ST20450) and a 32-bit bus with a standard 72-pin DRAM SIMM module
>>> (4-16M); 4 RS-232 ports; USB (Universal Serial BUS) controller; MIDI...
>>> Of course not all is needed by everyone, only the FPGA can be mounted
>>> in a minimal version, and it can be a PGA, so no trouble soldering it.
>>> You can easily implement any kind of UART in a reasonabily big chip.
>>> Probable costs (for the user):
>>> development and testing ... $0
>>> FPGA ... $50-$100
>>> PCB ... $1200/n_users
>>> uP(20450) ... $40
>>> uP(56000) ... $0
>>> RAM ... see your local store/get from an old PC
>>> Connectors, glue logic ... $10
>>>
>>> Any feedback?
>
> Hmmm.. I just attempted a project like this for as my "Senior Design
> Project." It failed miserably. Primary reasons: PCB layout software
> is too expensive and possibly difficult to use (this may not be an
> issue if you are sending it somewhere to have done), and designing a
> DRAM/bus controller in an FPGA is a b*tch (really, its no picnic).
>
> Also, an FPGA that is designed to interface with all of the sh*t (excuse
> me) that have piled on that board is going take HOURS (and hours, and hours)
> to design and test. This project would be difficult enough (IMHO) if
> you just had a pile of 64kx8 DRAM chips and a simple dumb logic circuit.
That is not a problem, because an experienced hardware designer
(not me!) will design the board. The only serious problem would
be assembly. The PCB design will be donated. PCB manufacture is
troublesome, but 4-layer boards can be built if enough people
are interested.
If you want a board, all you need to do is:
Request it.
Wait for the design.
Pay for the PCB & misc. parts (about $200 I guess)
Get some RAM.
Solder the board.
That assumes enough people want boards.