[fpc-pascal] Parallel Port Access with Free Pascal - windows

[Mark Morgan Lloyd]

James Richters wrote:

I was rather rushed earlier for reasons that would probably amuse but 
would be vastly OT (shoving sheep around Sussex since we're shearing 
Saturday...).

> I like the looks of that Velleman K8055,  that would do the job for me if I
> can get it to work.   I would actually prefer a linux port of my program

The Velleman boards usually come as kits, but they use PTH components 
and are a doddle to assemble. My recollection is that the K8055 came 
with something crude that allowed you to interface from e.g. Visual 
Basic, however I found that somebody had reverse-engineered it and 
produced a library (?) for Linux... I can't remember whether this was C 
or Pascal. I used this with Lazarus (the IDE and class library that sits 
on top of FPC) to produce something similar to Velleman's own demo app, 
you'd obviously be welcome to this.

However in the general case I think it would be worth bearing in mind 
that functionality of the Velleman board could fairly easily be 
implemented using appropriate firmware on an Arduino, and this is likely 
to be more "future proof" than a demo kit. But I don't have any ready 
URLs etc.

> however I keep hitting a roadblock when I try to use the graph unit.  My
> program used the turbo pascal graph unit exclusively for it's user interface
> and I'm trying to avoid re-writing the entire thing.  It works fine in
> windows, but when I try to run it on linux I can't get it to compile, it
> can't find the graph unit.  I may have some directories set wrong or
> something, I'm not sure, but that's what's holding me up on a linux port.

Can't comment on that, but I see Graham's lending a hand. Particularly 
if you're porting to Linux you do need to consider whether you're 
planning to run in the context of a GUI or over SSH etc, what /exactly/ 
are you trying to display and on what sort of system?

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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