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

Marc Santhoff M.Santhoff at web.de
Thu Jul 21 05:29:26 CEST 2016

On Fr, 2016-07-15 at 14:59 -0700, Zaaphod wrote:
> I am trying to get access to the parallel port with Free Pascal.  
> I'm trying to use this version of inpout32 (x64)
> http://www.highrez.co.uk/downloads/inpout32/ 
> Here's my program:
> http://pastebin.com/facf6EFc
> Here's my Unit:
> http://pastebin.com/XR0aYUPR
> When I try to run it, I get a windows message The application was unable to
> start correctly (0xc000007b). click ok to close the application.

You could search Microsofts web site to decode this error.

> then  I get Exitcode 123 in the Free Pascal IDE.  123 is decimal of 7b.
> Does anyone know how to get this to work?   reading and writing the parallel
> port used to be so easy, now it's extremely confusing, thanks windows!

Didn't test, but as a remark: parallel port is dead and it has been a
constant source of problems. First the access rights problems you know
of. Second it has no fixed timing, so you're in trouble when e.g.
flashing a microcontroller works on one machine and refuses to on
another one. Third it is not electrically protected, if you fry it, the
mainboard is dead by chance or you have to insert an extension board -
which is hard to find nowadays, too.

Depending on your needs I'd suggest using a USB-to-serial-Adapter or
similar. They are cheap and well supported (e.g. using CP2102). As an
alternative FTDI has some nice USB-to-anything (including parallel)
chips and they sell modules with mil spacing pins for easy

HTH somehow,

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