Re: Apple //e's RGB Card To Apple IIgs' RGB Monitor

["Alex Freed" <alexf@mirrow.com>]

"mdj" <mdj.mdj@gmail.com> wrote in message
1166714975.805034.160910@79g2000cws.googlegroups.com">news:1166714975.805034.160910@79g2000cws.googlegroups.com...

> Thanks, but not really. I've been doing FPGA work with VHDL/Verilog for
> a while - I was more interested in the development process for
> GALS/PALS

In the Dark Ages the fuse maps were calculated by hand. Then PALASM was
invented.
You would write equasions in the form of sum of products.

RES5 = /A0*A1*/A2*/A3 + B0*B1

RES5 is true when A=5 or both B0 and B1 are "1".

The next step was ABEL. A higher level language. Use Google if interested.

At the same time the (free) Icarus Verilog  has an option of setting a
PAL/GAL as a target.
A lot of other tools can do the same. A GAL is just a smaller CPLD.

-Alex.