Am Montag, 21. April 2003 22:15 schrieb Bob Tanner:
> On Sunday 20 April 2003 07:08 pm, Sven Heithecker wrote:
> > Hi,
> >
> > I am currently new to parport/EPP programming and need some startup-help.
> > I need to access the PC's parport in EPP mode. It's going to be a
> > "static" solution, so no drivers etc are needed, just plain access to the
> > port. Currently I am trying something like
> >
> > int mode = IEEE1284_MODE_EPP;
> > if( (fd_par = open("/dev/parport0",O_RDWR)) == -1 ) error(...)
> > if(ioctl(fd_par,PPCLAIM)) error(...)
> > if(ioctl(fd_par,PPNEGOT,&mode)) error(...)
> >
> > and then simple access using read(fd_par,...) and write(fd_per,...).
> > However, so far the program stopps at the EPP negotiation with an I/O
> > error. I activated EPP in the BIOS, but when looking at
> > /proc/sys/dev/parport0, it say that no IRQ or DMA channels are assigned
> > and that EPP is not possible.
>
> Try turning on debugging in the parport module?
>
> I'm not sure if this is the proper way, but I edited:
> ieee1284_ops.c
> ieee1284.c
> parport_pc.c
> And changed the #undef DEBUG to #define DEBUG
> And I hardcoded static int verbose_probing = 1 into parport_pc.c:97
> I have the parallel port stuff compiled into, but if you are doing modules
> I believe you can do something like this in your /etc/modules.conf:
> alias parport_lowlevel parport_pc verbose_probing=1
> Or modprobe parport_pc verbose_probing=1
Hi,
thank you for that, I changed the options in modules.conf (already got that
idea by myself ;-) ) and now It says indeed in /proc/sys/dev/parport0/modes
that EPP is available, but the program still fails at EPP negotiation.
Regards,
Sven Heithecker
-- Sven Heithecker sven.heithecker@web.de Pestalozzistr 6 Fax 0531-3489815 38114 Braunschweig Tel 0531-336580-- To unsubscribe, send mail to: linux-parport-request@torque.net -- -- with the single word "unsubscribe" in the body of the message. --
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