[Coco] fpga coco

[Mark McDougall]

On 21/02/2014 12:19 PM, camillus.b.58 at gmail.com wrote:

> So what i’m saying is that with all the knowledge that most of you
> guys have concerning fpga, would it not be smart to make models of the
> gime chip and cpu , so that those chips can be replaced whenever they
> fail.

Firstly, it is certainly possible to design the components within the FPGA
to be 'pin compatible' in effect with the real devices. So it's *possible*
that the IP is already suitable for such an application. However, there
are design issues within an FPGA that may mean that certain designs are
NOT suited at all. It would have to be evaluated on a case-by-case basis.

Secondly, using an FPGA as a 'drop-in' replacement isn't exactly a trivial
exercise. FPGA's require multiple, non-5V, power rails, and are generally
a bit fussy about noise and grounding on the circuit board around them.
They also require clocking. So it becomes quite an expensive exercise.
More practical is using a CPLD, and in fact most chips could be adequately
emulated in a CPLD rather than requiring an FPGA.

MikeJ from FPGAARCADE.COM offers PLD replacement parts for a bunch of
custom arcade-related IC's, for example, plus bare 'adapter' boards for
those that want to roll their own.

Regards,

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