| 33,7 → 33,8 |
|---|
| * Linux i2c does not include this bit in this address, so the actual |
| * address is 0xC0 shifted down, 0x60. |
| */ |
| #define CMPS03_ADDR 0x60 |
| #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 |
| 45,7 → 46,7 |
|---|
| int main(int argc, char *argv[]) { |
| char *end; |
| int res,file; |
| int e1; |
| int error; |
| char filename[20] ; |
| long funcs; |
| |
| 52,45 → 53,54 |
|---|
| int heading_byte, heading_word_h, heading_word_l; |
| int bearing_long, bearing_degrees; |
| |
| sprintf(filename,"/dev/i2c-%d"); |
| if ((file = open(filename,O_RDWR)) < 0) { |
| e1 = errno; |
| if (e1 != ENOENT) { |
| fprintf(stderr,"Error: Could not open file '%s' : %sn", |
| filename,strerror(e1)); |
| if(e1 == EACCES) |
| fprintf(stderr,"Run as root?n"); |
| 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) { |
| if (errno == EBUSY) { |
| printf("device is busyn"); |
| } |
| printf("Got error: %d\n", errno); |
| exit(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 = i2c_smbus_read_byte_data(file, CMPS03_SOFTWARE_REVISION); |
| res = read(file, CMPS03_SOFTWARE_REVISION,1); |
| if (res < 0) { |
| printf("Cannot read software revision leveln"); |
| printf("Cannot read software revision level \n"); |
| } else { |
| printf("Software revision level: %02xn", res); |
| 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 = i2c_smbus_read_byte_data(file, CMPS03_BEARING_BYTE); |
| if (heading_byte < 0) { printf("Error reading from compass."); exit(1);} |
| 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 = i2c_smbus_read_byte_data(file, CMPS03_BEARING_WORD_HIGH); |
| if (heading_word_h < 0) { printf("Error reading from compass."); exit(1);} |
| heading_word_l = i2c_smbus_read_byte_data(file, CMPS03_BEARING_WORD_LOW); |
| if (heading_word_l < 0) { printf("Error reading from compass."); exit(1);} |
| 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; |