Very Computer

by **andrew shelle** » Wed, 27 Oct 1999 04:00:00

I have a number of programs written in Borland C for Dos which I want to
convert to Linux. Many of these programs address the hardware ports, using
the
Borland functions INP and OUTP. Are there equivalent functions available in
the standard Linux C , or do I need to use some form of assembly code ? If
anybody can answer this, a few example lines would be much appreciated.

by **Ludovic Boissea** » Wed, 27 Oct 1999 04:00:00

> I have a number of programs written in Borland C for Dos which I want to
> convert to Linux. Many of these programs address the hardware ports, using
> the
> Borland functions INP and OUTP. Are there equivalent functions available in
> the standard Linux C , or do I need to use some form of assembly code ? If
> anybody can answer this, a few example lines would be much appreciated.

Try to use the devices in /dev , it's the usual way to access the
hardware, such
as sound cards ( try cat sound.au > /dev/audio ) or RS-232...

Good luck.

Ludo, alias "Le Ludal"

_________________________________________________________________

Ludovic BOISSEAU Membre Elingsys
Elve ingenieur Esil / Es2i Promotion 2001

_________________________________________________________________

by **Daniel Robert Frankl** » Wed, 27 Oct 1999 04:00:00

>I have a number of programs written in Borland C for Dos which I want to
>convert to Linux. Many of these programs address the hardware ports, using
>the
>Borland functions INP and OUTP. Are there equivalent functions available in
>the standard Linux C , or do I need to use some form of assembly code ? If
>anybody can answer this, a few example lines would be much appreciated.

Check out the I/O port programming HOWTO:

http://metalab.unc.edu/pub/linux/docs/HOWTO/mini/IO-Port-Programming

but in short, if you aren't using a driver, you need to do this:

#include <asm/io.h>
#include <stdio.h>

#define IOBASE 0x31C

int main ()
{
char C;
char data = 0xAB;

if (ioperm (IOBASE, 2, 1) == -1) /* gets i/o permissions for 2 ports starting at IOBASE */
fprintf (stderr, "Can't get permission\n");
return -1;
else {
outb (data, IOBASE); /* sends a byte */
C = inb (IOBASE + 1); /* reads a byte */
printf ("C = %i\n", (unsigned int) C);
return 0;
}

Quote:}

There are also inw and outw macros as well for 16-bit I/O.

Compile with -O (must have optimisation turned on!) and either run it as
root or make it setuid root (thats why it is better to write a device
driver).

HTH,

- Daniel
--
******************************************************************************
* Daniel Franklin - Postgraduate student in Electrical Engineering

******************************************************************************

by **gra..** » Wed, 27 Oct 1999 04:00:00

> I have a number of programs written in Borland C for Dos which I want to
> convert to Linux. Many of these programs address the hardware ports, using
> the
> Borland functions INP and OUTP. Are there equivalent functions available in
> the standard Linux C , or do I need to use some form of assembly code ? If
> anybody can answer this, a few example lines would be much appreciated.

I am also in the process of doing this task, and from a few recommendations,
the best I have found so far IMHO is located at
/usr/doc/HOWTO/mini/IO-Port-Programming.html in your distribution. There's
also a Serial HOWTO, but I think it's too bulky and unexplanative to use at
the first time.

Or is it that I get crazy after reading ten lines of text? :-)

Gogosoftware - http://welcome.to/gogosoftware/

WinError 01F: Reserved for future mistakes of our developers.

Very Computer

Accessing hardware ports

Accessing hardware ports

Accessing hardware ports

Accessing hardware ports

Accessing hardware ports