A plan for a "universal" low-pin-count programmer

[Alexandre Souza]

> I know a few folks here (besides myself) have accumulated collections of
> older-generation (i.e. "obsolete") fuse-PROMs, GALs, PALs, and so on. A 
> common
> complaint is that modern programmers won't touch these devices -- negative
> voltages (sometimes very high negative voltages) are required to program 
> some
> of them, and for others the programming hardware just wasn't tested with 
> them.

    Philip, maybe you should update your knowledge on modern programmers :o) 
There are three kinds of programmers you can use on that

    - Old ISA and parallel port programmers. It is easy to find an ALL-03A 
or something like that, that programs even 1702.
    - Modern home-built programmers - Willem/Willem USB come to mind. It 
doesn't touch proms, gals, pals, but programs most everything else.
    - Modern el-cheapo USB programmers from China. I have a wellom 
programmer that programs everything but old 87xx and anything below 2716, 
but do all kinds of GALs, PALs, PROMs and like. There is a more expensive 
model that programs everything but I thought (WRONG!) that I'd never need 
that.

> In my experience, when confronted with the fact that their programmers 
> don't
> actually work, most programmer manufacturers seem to respond by asking why
> you're even thinking about using 1702 EPROMs in their programmer, and
> sooner-or-later admit that they actually didn't test them on anything more
> recent than a programmer they last sold in the late 1980s, and that they 
> "just
> ported the software across and thought it would work".

    You're asking the wrong manufacturer. Try that with Elnec. You'll have a 
great and pleasurefull surprise :)

> A completely open-sourced device programmer. That is, all the hardware
> designs, PCB layouts, software and firmware are (or at least will be)
> completely open. My "rough feature set" boils down to:

    Willem USB anyone?

>   * 24, 32 or 40 individually-programmable pin drivers. More or less if 
> you
> like -- add or remove a few pin drivers. I think the upper maximum is 
> likely
> to be around 64 pins, based on typical CPLD pin counts.

    You hardly use 40, the best designs today uses 48