Parallel Port eprom programmers - suggestions

[Andrew K. Mattei]

Roger Heflin wrote:
> 
> I am lazy and those are fairly cheap and I really cannot do a better
> job than the ones I can buy.

I understand... But, for my scenario, first baby came 2 months ago, wife
left her job to take care of him, so, gotta minimize car expenses... for
now... ;^D and I can't exactly spend a lot of time these days banging
away on the grubby '79 Camaro in the garage while babysitting. ;)
Soldering and programming while babysitting, though - that's easy!

>  And I also have need to read some much
> larger eproms for some people I work with.

Completely understandable. The design I was working from did the 32-pin
EPROMs as well - but I made the decision to stick with the 28s. So, mine
will go up to 512's.

> 
> Qbasic is nice for simple tasks.

Yeah, if it gets too messy, I'll go to C. Qbasic is quick and dirty,
though. 

> The parallel port programmer I found claims to work on almost any
> parallel port made.

I guess it depends on how it's designed...

The first one I built (off of a design on the 'net) used the
bidirectional properties of the 8 data pins (at 0x378, pins 2-9 on the
port). 3 out of the 4 computers I tried it on, it didn't work at all.
The other one - I couldn't get two "reads" the same. Some computers
don't take too well to this port being bidirectional. The way I designed
this new one, I use the 5 bits on the standard LPT input port (at
0x379), and use the other 2 addresses (8 bits at 0x378 and 4 bits at
0x37A) as outputs. To me, nothing is really new here - I've done several
control programs before using the LPT port. So it's really not that
tough. :) If I get really industrious, I could do it in VB... But, I'm
all for quick and dirty when doing things like this for myself... ;)
Some places I won't skimp, but some, I will...

-Andrew