A thought...

[tom cloud]

>> From: Arnaldo Echevarria <aec at ao.net>
>> 
>> I'm thinking, instead of going the 68hc11 route, using a pc.  Instead of
>> building a a/d and d/a board, use two parallel ports.  That would give me
>> 8 ins and 8 outs.  Timing would be resolved by the computer, hell, 386/486
>> motherboards are cheap.
 (snip )
>I've done a fair amount of PC-based real-time control.  The biggest 
>obstacle you'll encounter is boot time.  Even with a flash disk, normal 
>PC BIOSs waste precious seconds checking everything umpteen times.

        [ snip ]

>If you can find a solid PC BIOS that boots in less than a second, I'd be 
>interested in it.
>--
>Chuck Tomlinson <tomlinsc at ix.netcom.com>

I haven't worked on process control or related in a while, but there
were always public domain OS's (and boot routines) available for
the 8-bit genre.  I'll bet if you look you'll find the same thing
exists for the 80x86 types.  The advantage is there's cheap hardware
already available.  You don't normally want all that DOS crap hanging
around your neck -- it's too unwieldy, it's for a different purpose.
There's too much stuff you don't need.  If you can find a simple OS
written to work on the PC hardware it'll make a great platform to
build any data logger, controller, etc.


Tom Cloud <cloud at peaches.ph.utexas>

None of the opinions expressed here are mine or anyone elses