Date: Mon, 28 Oct 2002 08:56:35 -0500 From: Joe Sunday <sunday@csh.rit.edu> To: David Nicholas Kayal <davek@saturn5.com> Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: i am looking for a 5 volt signal Message-ID: <20021028135635.GA28293@csh.rit.edu> In-Reply-To: <Pine.BSF.4.44.0210270911490.329-100000@blackbox.yayproductions.com> References: <Pine.BSF.4.44.0210270911490.329-100000@blackbox.yayproductions.com>
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On Sun, Oct 27, 2002 at 09:12:33AM -0800, David Nicholas Kayal wrote:
> I'm looking for a 5 volt signal.
>
> I have wires plugged into pins 2 and 25 of the parallel port.
>
> I have written a small program:
>
> #include <stdio.h>
> #include <dev/ppbus/ppi.h>
> #include <dev/ppbus/ppbconf.h>
>
> int main()
> {
> int fd;
> while(1)
> {
> ioctl(fd, PPISDATA, 255);
> }
> }
PPISDATA actually takes an int* argument. (The man page may be a tad
confusing here.)
Try
int main() {
int fd;
int d = 255;
fd = open( "/dev/ppi0", O_RDWR );
ioctl( fd, PPISDATA, &d );
return 0;
}
The port should hold the last value you send to it, there's no need
to continually refresh it.
--Joe
--
Joe Sunday <sunday@csh.rit.edu> http://www.csh.rit.edu/~sunday/
Computer Science House, Rochester Inst. Of Technology
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