[cctalk] Re: Good C to FPGA/PLA compiler

[Paul Koning via cctalk]

> On Sep 22, 2023, at 3:07 PM, Chuck Guzis via cctalk <cctalk@classiccmp.org> 
> wrote:
> 
> On 9/22/23 11:34, emanuel stiebler via cctalk wrote:
> 
>> There are still some 84pin chips out there(Altera & Xilinx). Sometimes
>> they are pulls, or some 5V tolerant xilinx xc95xxxxl
> 
> I still have a few 84 pin PLCC XC95108 5V CPLDs  Originally, I did a
> tape controller design with one before Xilinx discontinued them.  I
> figured that using a discontinued part was not the way forward, so I
> dropped the project.   Xilinx did/does have its ISE design suite, which
> is fairly easy to use.
> 
> Eventually, it turned out that using a reasonably fast MCU with 5V
> tolerant I/O worked just as well and avoided the "mystery in a chip" of
> a CPLD.

I used an Arduino Feather that way, for my PS-2 to LK201 converter.  And while 
not 5V tolerant, a Raspberry Pico is a particularly powerful and cheap option; 
one of my projects could run DDCMP at 10 Mb/s including the "integral modem" 
compatible signaling.

As I mentioned, 5V tolerant inputs can, at least for not too high speeds, be 
done simply by resistive voltage dividers.

        paul