Byron A Jeff wrote:

>> Two years ago when I bought my laptop, I also bought a pcmcia parallel
>> port card. It was expensive, but it's a real parallel port. I imagine
>> in the future someone will make a USB version that takes hold in the
>> marketplace and be more affordable.
> 
> Interesting idea. However, with parts like the FTDI 245 parallel, or
> even 18F USB PICS, that conversion isn't going to be impossible. But
> espeically with the PICs it'll be kind of difficult to bootstrap if you
> have to obtain a USB PIC programmer for the sole purpose of dumping code
> into the part. 

This was an interesting discussion. Let me add a thought here... This about
someone starting a hobby, right? When you're starting with electronics, you
need to buy some tools and you don't have a junk box yet, so most of the
parts you'll need you have to buy, too. It's assumed that you have a
computer, or else you'll have to buy that one, too. So maybe we just
consider a pre-programmed PICs (programmer core, or a port wiggler) or a
parallel port adapter one of those tools you buy? 

OTOH (and I need to add here that I don't have a clue about the programming
specs -- a detail I never was too curious about :) if the programming spec
is static or at least has wide enough timing specs so that it can be done
/very/ slow, the modem control signals of a USB-to-serial adapter should
work. They can't be relied upon for quick timing, but they are probably
good enough for timing in the tens or hundreds of milliseconds. Programming
one byte per second is good enough for such a bootstrapper programmer.
This, controlled by a PC software written in a highly portable language,
could do it, couldn't it? Of course this violates James's "no software"
condition, but I'm not sure how important it is. "Highly portable" should
be good enough. And probably the only parts that are platform-dependent are
some means to control timing in the 100s of ms and how to wiggle the modem
control lines. If the programming specs allow such slow programming...

Gerhard

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