[fpc-pascal]Yet another impossible task

Jérémie LEFRANCOIS j.lefrancois at altran-tech.net
Thu Sep 9 10:58:25 CEST 2004


Yes, you got the point.
This works fine if you remove the "uses crt" clause.
Thanks. And thanks to Stefan Becker as well.

En réponse à Thomas Schatzl <tom_at_work at gmx.at>:

> Hello,
> 
> Jérémie LEFRANCOIS schrieb:
> > I would be very happy to solve the following problem, any suggestion
> is welcome.
> > I work with MS-DOS 6.2, trying to port from TP55 to Freepascal GO32.
> > There is a terminate stay resident program (for which I have no access
> to the
> > sources) that deals with the interface part of the application
> (GUI).
> > It is started and installed at boot time (remember the old
> autoexec.bat).
> > It is the acceessed by just writing to the screen sequences with a
> special begin
> > sequence and end sequence. To put it more simply, in order to open a
> window the
> > Pascal program must issue a writeln('#19#254#1,'open window
> mywindow.aid',#1);
> > I want to avoid writing over again all the screen managing routines.
> > 
> > Of course I know that the TSR concept is 16 bits and that freepascal
> works in 32
> > bit.
> > 
> > Any ideas ?
> 
>  From your description the TSR program seems to intercept DOS-interrupt
> 
> 21h and interpretes the given data if it goes to the standard output 
> (just a guess - maybe wrong :)
> 
> You can verify this if you set 'directvideo := true;' in the TP5.5 
> program (if it uses CRT) and interacting with the TSR should not work 
> anymore ;-)
> [Not sure if there's already this flag in TP 5.5 CRT unit]
> 
> So *if* this is the case, the TSR should already work with FPC programs
> 
> that don't use the CRT unit. This is because the CRT unit basically 
> always does direct writing to the video memory, bypassing the DOS 
> interface similar to when 'directvideo := true' in TP.
> 
> You can try by making a simple example program which does not use CRT 
> trying to send some data to the TSR.
> If this works, you only have to redo the parts of the CRT unit which 
> assume direct memory access and are required by your program. I think 
> this is easier than doing the windowing stuff.
> 
> But, then again, I'm just guessing....
> 
> Regards,
>    Thomas
> 
> 
> _______________________________________________
> fpc-pascal maillist  -  fpc-pascal at lists.freepascal.org
> http://lists.freepascal.org/mailman/listinfo/fpc-pascal
> 



__________________
Jérémie Lefrançois
06 73 27 35 97 
Consultant 
Altran Technologies




More information about the fpc-pascal mailing list