WebSVN – svnkaklik – Diff – /programy/Atmel32_C/cmps03/compass.c

 /* compass.c
  *
  * Software to read from the CMPS03 magnetic compass.
  *
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
- * By Josh Marshall, joshua dot marshall at studentmail dot newcastle dot edu dot au
+#include <unistd.h>
- * October 15, 2004.
+#include <fcntl.h>
+#include <linux/i2c-dev.h>
- *
+/* Note that the documentation for the compass states its address as 0xC0.
- * Adapted from code for the SP03 speech synthesiser
+ * However, this includes the low bit which specifies read or write.
+ * Linux i2c does not include this bit in this address, so the actual
- * By Bram Stolk, b.stolk at chello.nl
+ * address is 0xC0 shifted down, 0x60.
- *
+ */
- * Bram Stolk's notes:
+#define CMPS_Addr	(0xC0>>1)
- * In linux, you can do I2C stuff in user-space, if you enable
+#define I2C_SLAVE	0x0B	/* Change slave address
- * the device-interface to i2c. You can use plain read() and
+/* The important registers on the compass. Internal/test registers omitted. */
+#define CMPS03_SOFTWARE_REVISION 0x0
+#define CMPS03_BEARING_BYTE 0x1
- * write() calls on your /dev/i2c-0 file.
+#define CMPS03_BEARING_WORD_HIGH 0x2
+#define CMPS03_BEARING_WORD_LOW 0x3
+#define CMPS03_CALIBRATE_CMD 0xF
- *
- * NOTE: Check if you have an i2c adapter active by doing:
+void I2C_addr (int Addr)  // vybere adresu cidla se kterym se bude komunikovat
- * cat /proc/bus/i2c
+{
- * If this comes up empty, then you have no adapters. If the
+    if (ioctl(file, I2C_SLAVE, Addr) == -1)
+    {
- * file does not exist at all, you probably lack i2c kernel
+        fprintf(stderr, "Failed to set address to 0x%02x.\n", Addr);
- * support alltogether.
+        exit(-5);
- */
+    }
+}
-#include <errno.h>
+int i2c_init()   // zinicializuje i2c
+{
-#include <string.h>
+	file = open("/dev/i2c-0", O_RDWR);
-#include <stdio.h>
+	if (file < 0)
+	{
-#include <stdlib.h>
+		cerr << "Could not open /dev/i2c-0." << endl;
-#include <unistd.h>
+		return -1;
+	}
-#include <fcntl.h>
+	return 0;
+}
+unsigned char read_azimut_mag()  // precte azimut z kompasu
+{
-#include <linux/i2c-dev.h>
+    char Buf[3];      // promena pro manipulaci s i2c
-/* Note that the documentation for the compass states its address as 0xC0.
+    I2C_addr(CMPS_Addr);
+    Buf[0]=1;
- * However, this includes the low bit which specifies read or write.
+    write(file,Buf,1);
- * Linux i2c does not include this bit in this address, so the actual
+    read(file, Buf,1);
- * address is 0xC0 shifted down, 0x60.
+    return (Buf[0]-SEVER);
- */
+}
-#define CMPS03_ADDR	0x60
-#define I2C_SLAVE	0x0B	/* Change slave address
-/* The important registers on the compass. Internal/test registers omitted. */
-#define CMPS03_SOFTWARE_REVISION 0x0
+void calib()  // kalibrace kompasu
-#define CMPS03_BEARING_BYTE 0x1
+{
-#define CMPS03_BEARING_WORD_HIGH 0x2
+    char Buf[3];      // promena pro manipulaci s i2c
-#define CMPS03_BEARING_WORD_LOW 0x3
-#define CMPS03_CALIBRATE_CMD 0xF
+    I2C_addr(CMPS_Addr);
+    Buf[0]=15;
+    Buf[1]=0xFF;
+    write(file,Buf,2);
+}
-int main(int argc, char *argv[]) {
+int main(int argc, char *argv[])
+{
    char *end;
    int res,file;
    int error;
    char filename[20] ;
    long funcs;
    int heading_byte, heading_word_h, heading_word_l;
    int bearing_long, bearing_degrees;
    sprintf(filename,"/dev/i2c-0");
    file = open(filename,O_RDWR);
    if (errno != 0)
    {
      switch (errno)
      {
      case EACCES:
          fprintf(stderr,"Run as root? \n");
          break;
      default:
          fprintf(stderr,"Error: Could not open file '%s' : %s \n", filename, strerror(errno));
          break;
      }
    }
    if (ioctl(file,I2C_SLAVE,CMPS03_ADDR) < 0) {
      switch (errno)
      {
      case EBUSY:
          printf("device is busy \n");
          break;
      default:
          printf("Got error: %s \n", strerror(errno));
          exit(0);
       }
    }
    /* Get software revision number */
    res = read(file, CMPS03_SOFTWARE_REVISION,1);
    if (res < 0) {
      printf("Cannot read software revision level \n");
    } else {
      printf("Software revision level: %02x \n", res);
    }
    /* Loop and read from the compass. */
    while (1) {
      /* The heading byte is 0-255 for the 360 degrees. */
      heading_byte = read(file, CMPS03_BEARING_BYTE,1);
      if (heading_byte < 0) { printf("Error reading from compass. \n"); exit(1);}
      /* The high resolution heading is given in two registers, and is 10 * the
       * heading in degrees, ie 359.9 degrees reads as 3599. */
      heading_word_h = read(file, CMPS03_BEARING_WORD_HIGH,1);
      if (heading_word_h < 0) { printf("Error reading from compass. \n"); exit(1);}
      heading_word_l = read(file, CMPS03_BEARING_WORD_LOW,1);
      if (heading_word_l < 0) { printf("Error reading from compass. \n"); exit(1);}
      /* Combine the two bytes, and get the heading in degrees. */
      bearing_long = heading_word_h * 256 + heading_word_l;
      bearing_degrees = bearing_long / 10;
      printf("Bearing: %d \n", bearing_degrees);
      /* Wait for a while. */
      usleep(200000);
    }
 }

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(root)/programy/Atmel32_C/cmps03/compass.c @ 394 – Rev 358 → 385