| 0,0 → 1,75 |
|---|
| //------------------------------ |
| // Low level routines |
| //------------------------------ |
| void hmc5883l_write_reg(int8 reg, int8 data) |
| { |
| i2c_start(); |
| i2c_write(HMC5883L_WRT_ADDR); |
| i2c_write(reg); |
| i2c_write(data); |
| i2c_stop(); |
| } |
| |
| //------------------------------ |
| int8 hmc5883l_read_reg(int8 reg) |
| { |
| int8 retval; |
| |
| i2c_start(); |
| i2c_write(HMC5883L_WRT_ADDR); |
| i2c_write(reg); |
| i2c_start(); |
| i2c_write(HMC5883L_READ_ADDR); |
| retval = i2c_read(0); |
| i2c_stop(); |
| |
| return(retval); |
| } |
| |
| //------------------------------ |
| typedef struct |
| { |
| signed int16 x; |
| signed int16 y; |
| signed int16 z; |
| }hmc5883l_result; |
| |
| // This global structure holds the values read |
| // from the HMC5883L x,y,z registers. |
| hmc5883l_result compass = {0,0,0}; |
| |
| //------------------------------ |
| void hmc5883l_read_data(void) |
| { |
| unsigned int8 x_lsb; |
| unsigned int8 x_msb; |
| |
| unsigned int8 y_lsb; |
| unsigned int8 y_msb; |
| |
| unsigned int8 z_lsb; |
| unsigned int8 z_msb; |
| |
| i2c_start(); |
| i2c_write(HMC5883L_WRT_ADDR); |
| i2c_write(HMC5883L_X_MSB_REG); // Point to X-msb register |
| i2c_start(); |
| i2c_write(HMC5883L_READ_ADDR); |
| |
| x_msb = i2c_read(); |
| x_lsb = i2c_read(); |
| |
| z_msb = i2c_read(); |
| z_lsb = i2c_read(); |
| |
| y_msb = i2c_read(); |
| y_lsb = i2c_read(0); // do a NACK on last read |
| |
| i2c_stop(); |
| |
| // Combine high and low bytes into 16-bit values. |
| compass.x = make16(x_msb, x_lsb); |
| compass.y = make16(y_msb, y_lsb); |
| compass.z = make16(z_msb, z_lsb); |
| } |
| |