[Coco] General question for the fpga guru's out there

[Mark McDougall]

On 3/01/2013 7:15 AM, camillus Blockx wrote:

> Well Frank, it sounds that this could be a nice project that just needs a
> coordinator to start with. If one person writes down what board to produce
> then all the HW gurus can start making schematics of just one part of the
> board. After all the parts of the schematic are done

Not really something that can be designed "by committee" IMHO. Choosing an 
FPGA also requires choosing I/O standards (voltage levels) for each I/O bank 
and that mandates which power rails are required. If you choose to design 
arbitrary circuits in isolation you'll end up with silly numbers of power 
supplies and even more ridiculous level conversion logic.

You'll also quickly chew up I/O pins on the FPGA with memory and legacy I/O 
connectivity options, and you'll end up using a massive BGA part that will 
be expensive and require commercial assembly.

It is also something that really should not be attempted without a 
reasonably good knowledge of how the Coco will be implemented in the FPGA. 
That will dictate what type of memory you'll require, what I/O, whether you 
need an external micro for floppy emulation, etc etc.

Again, not really in the same league as sticking a PIC on a 2-layer PCB.

Regards,

-- 
|              Mark McDougall                | "Electrical Engineers do it
|  <http://members.iinet.net.au/~msmcdoug>   |   with less resistance!"