trossin wrote:
> Right on about the FPGAs.   They cost a great deal of money and since they
> are not available in "proven through hole technology" making a one off
> prototype is even more money.
>
> The goal of the project was to keep the cost way down so other people could
> reproduce it and to keep the bus interface the same so that others could get
> the feel of retro computing.   The PICs I used were $6 and I was able to
> plug them into a solderless breadboard.  The cheapest FPGA solution I've
> seen is well over $100 unless you are willing to create a custom PC board
> which again is another $75 but you will need a PC board anyway to implement
> the other logic.  
>
>
>   
I think Spartan 3E is about $15? Not sure quantity.
If you buy 10 PCBS, a double sided PCB 100mm x 100mm may be under $15

You can buy  mini-PCB  with FPGA pre-mounted.

A BGA rework station is a once off cost.

You can get PCB adaptor and mount TQFP up to 60 pins using a 2mm tip 
soldering iron.

I'd agree it's a fun achievement to use a 18F for this. Given negligible 
price  difference I'd go for 18F.

VHDL and the Xilinx tools are probably easier than PIC assembler though 
:-) But it's not Programming as you know it, Jim. :-D

But 8bit PIC is retro computing. It's a 1977 design. I remember by late 
80s you could get 20MHz Z80 as  "core" in an ASIC. Hitachi did a Z80 
with MMU for 512k and some I/O too?

x86 and ARM are practically Retro now :)
 
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