comedilib/demo/dio.c

/*
 * Digital I/O example
 * Part of Comedilib
 *
 * Copyright (c) 1999,2000 David A. Schleef <ds@schleef.org>
 *
 * This file may be freely modified, distributed, and combined with
 * other software, as long as proper attribution is given in the
 * source code.
 */
/*
 * Requirements:  A board with a digital I/O subdevice.  Not just
 *    a 'digital input' or 'digital output' subdevice, but one in
 *    which the channels can be configured between input and output.
 */

#include <stdio.h>
#include <comedilib.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <getopt.h>
#include <ctype.h>
#include "examples.h"


comedi_t *device;

int main(int argc, char *argv[])
{
	int ret;
	int stype;
	struct parsed_options options;

	init_parsed_options(&options);
	parse_options(&options, argc, argv);

	device = comedi_open(options.filename);
	if(!device){
		comedi_perror(options.filename);
		exit(-1);
	}

	stype = comedi_get_subdevice_type(device, options.subdevice);
	if(stype != COMEDI_SUBD_DIO){
		printf("%d is not a digital I/O subdevice\n", options.subdevice);
		exit(-1);
	}

	printf("configuring pin %d on subdevice %d ", options.channel, options.subdevice);
	if(options.value)
	{
		printf("for output.\n");
		ret = comedi_dio_config(device, options.subdevice, options.channel, COMEDI_OUTPUT);
	}else
	{
		printf("for input.\n");
		ret = comedi_dio_config(device, options.subdevice, options.channel, COMEDI_INPUT);
	}
	if(ret < 0){
		comedi_perror("comedi_dio_config");
		exit(-1);
	}
	return 0;
}