hmc5883l.c

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>

#include <linux/i2c-dev.h> 
#include <fcntl.h>
#include <sys/ioctl.h>

static void 
HMC5883L_write(
	unsigned char address,
	unsigned char data,
	int fd)
{
	unsigned char buf[2];
	buf[0] = address;
	buf[1] = data;
	if((write(fd,buf,2))!=2) {
		printf("Error writing to i2c slave\n");
		exit(1);
	}
	return;
}
  
static unsigned char 
HMC5883L_read(
	unsigned char address,
	int fd)
{
	unsigned char buf[1];
	buf[0] = address;
	if((write(fd,buf,1))!= 1){
		printf("Error writing to i2c slave\n");
		exit(1);
	}
	if(read(fd,buf,1)!=1){
		printf("Error reading from i2c slave\n");
		exit(1);
	}
	return buf[0];
}

static void 
HMC5883L_readData(
	int *idata,
	int fd)
{
	unsigned char i,addr,data[6];
	for(i=0; i<6; i++){
		addr = 0x03 + i;
		data[i]=HMC5883L_read(addr,fd);
	}
	idata[0]=((int)data[0]<<24|(int)data[1]<<16)>>16;
	idata[1]=((int)data[2]<<24|(int)data[3]<<16)>>16;
	idata[2]=((int)data[4]<<24|(int)data[5]<<16)>>16;
	return;
}

static void
HMC5883L_init(int fd)
{
	unsigned char data;
	data = HMC5883L_read(0x0a,fd);
	if (data != 0x48) {
		printf("Identification Register 0x0a check failure [%02x]",data);
		exit(1);
	}
	data = HMC5883L_read(0x0b,fd);
	if (data != 0x34) {
		printf("Identification Register 0x0b check failure [%02x]",data);
		exit(1);
	}
	data = HMC5883L_read(0x0c,fd);
	if (data != 0x33) {
		printf("Identification Register 0x0c check failure [%02x]",data);
		exit(1);
	}
	HMC5883L_write(0x00,0xe0,fd); /* set default val to Config Reg A */
	HMC5883L_write(0x02,0x00,fd); /* set continuous mode to Mode Reg */
	return;
}
 

int
main(
	int argc,
	char **argv)
{
	int i,j,fd,data[3];
	char *i2cfile = "/dev/i2c-1"; 
	unsigned char i2caddr,status;
	double x,y,z;

	i2caddr = 0x1e;
	
	if ((fd = open(i2cfile, O_RDWR)) < 0) {
		printf("Faild to open i2c port\n");
		exit(1);
	}
	if (ioctl(fd, I2C_SLAVE, i2caddr) < 0) {
		printf("Unable to get bus access to talk to slave\n");
		exit(1);
	}

	HMC5883L_init(fd);
	
	x = y = z = 0;
	for(i=0,j=0; i<1000; i++) {
		status = HMC5883L_read(0x09,fd); 
		if (status | 0x1) {
			HMC5883L_readData(data,fd); 
			x += (double)data[0];
			z += (double)data[1];
			y += (double)data[2];
#if 0
			printf("x[%05d] z[%05d] y[%05d]\n",
				data[0],data[1],data[2]);
#endif
			j++;
		}
		usleep(1000*10);
	}
	printf("%5.1lf %5.1lf %5.1lf\n",x/j,y/j,z/j);
	return;
}

hmc5883l.rb

# coding:utf-8
 
require "pp"
require "net/https"
require "fileutils"
 
def xively(x,y,z)
  uri = URI.parse('https://api.xively.com/v2/feeds/1679002984.xml')
  
  https = Net::HTTP.new(uri.host,uri.port)
  https.use_ssl = true
  headers = {
    'X-ApiKey' => 'XXXXXXXXXXXXXXXXXXXXXXXXXXXX',
    'Content-Type' => 'application/xml'
  }
  data =<<-EOS
  <?xml version="1.0" encoding="UTF-8"?>
  <eeml>
    <environment>
      <data id="HMC5883L_X">
        <current_value>#{x}</current_value>
      </data>
      <data id="HMC5883L_Y">
        <current_value>#{y}</current_value>
      </data>
      <data id="HMC5883L_Z">
        <current_value>#{z}</current_value>
      </data>
    </environment>
  </eeml>
  EOS
  res = https.send_request('PUT',uri.request_uri,data,headers)
end
 
now = Time.now
dir = File.expand_path(File.dirname(__FILE__))
command = File.join(dir,"hmc5883l")
x,y,z = `#{command}`.split(" ")

exit 0 unless x && y && z

dir = File.join(ENV["HOME"],"hmc588l",now.strftime("%Y"),now.strftime("%m"))
file = File.join(dir,now.strftime("%d")+".txt")
FileUtils.mkdir_p(dir)

mode = File.exists?(file) ? "a" : "w"
File.open(file,mode) do |io|
  out = "#{now.strftime("%Y%m%d%H%M%S")}\t#{x}\t#{y}\t#{z}"
  io.puts out
end
 
begin
  xively(x,y,z)
rescue Exception => ex
  puts ex
end