Problem while using MPU6050
Posted: Thu May 24, 2012 11:52 am
Hi,
I have designed my own board. It has MPU6050 connected on I2C1 bus (No other sensors are connected on this bus). I am able to connect and communicate through I2C1 with sensor, but it seems that I am not getting value as per expected. Getting value exactly half of expected output.
This is start up part. Have set accelerometer range as +/-2g. So Z axis output should be around 16000 count. But I am getting exactly half of that. Tried changing range as well but same problem at rest of configuration as well.
Following function I am using to fetch data from MPU.
Any idea what am I doing wrong?
I have designed my own board. It has MPU6050 connected on I2C1 bus (No other sensors are connected on this bus). I am able to connect and communicate through I2C1 with sensor, but it seems that I am not getting value as per expected. Getting value exactly half of expected output.
This is start up part. Have set accelerometer range as +/-2g. So Z axis output should be around 16000 count. But I am getting exactly half of that. Tried changing range as well but same problem at rest of configuration as well.
Code: Select all
#define MPU_addr 0b1101001
void set_mpu_i2c(void){
uint8_t sampling_rate = 0x19, config = 0x1A, gyro_config = 0x1B, accel_config = 0x1C,txbuf[20],rxbuf[20];
txbuf[0] = 0x74;
//int16_t val1 = 0, val2 =0, val3 = 0, val4 = 0, val5 = 0, val6 = 0;
/* chprintf((BaseChannel *)&SD1, "abcd");
i2cMasterTransmit(&I2CD1, MPU_addr, txbuf, 1, rxbuf, 2);
chprintf((BaseChannel *)&SD1, "Who AM I %x, %x \r\n", rxbuf[0], rxbuf[1]);
chThdSleepMilliseconds(10);
*/
txbuf[0] = 0x6B;//pwr management 1;
txbuf[1] = 0x01;
i2cMasterTransmit(&I2CD1, MPU_addr, txbuf, 2, rxbuf, 0);
chThdSleepMilliseconds(1000);
txbuf[0] = 0x1B;//Gyro Config;
txbuf[1] = 0x00;
i2cMasterTransmit(&I2CD1, MPU_addr, txbuf, 2, rxbuf, 0);
chThdSleepMilliseconds(1000);
txbuf[0] = 0x1C;//Accel Config;
txbuf[1] = 0x00;
i2cMasterTransmit(&I2CD1, MPU_addr, txbuf, 2, rxbuf, 0);
chThdSleepMilliseconds(1000);
txbuf[0] = 0x19;//sampling_rate;
txbuf[1] = 0x09;
i2cMasterTransmit(&I2CD1, MPU_addr, txbuf, 2, rxbuf, 0);
chThdSleepMilliseconds(1000);
txbuf[0] = 0x19;
i2cMasterTransmit(&I2CD1, MPU_addr, txbuf, 1, rxbuf, 4);
chprintf((BaseChannel *)&SD1, "Reading config I %x, %x, %x, %x \r\n", rxbuf[0], rxbuf[1], rxbuf[2], rxbuf[3]);
chThdSleepMilliseconds(1000);
}Following function I am using to fetch data from MPU.
Code: Select all
void read_mpu_data_i2c(void)
{
uint8_t txbuf[20], rxbuf[20],i=0,j=0 ;
int16_t val[10];
txbuf[0] = 0x3B;
for(i=0;i<20;i++)rxbuf[i] = 0x00;
i2cMasterTransmit(&I2CD1, MPU_addr, txbuf, 1, rxbuf, 14);
val[0] = (rxbuf[0] << 8) + rxbuf[1];
val[1] = (rxbuf[2] << 8) + rxbuf[3];
val[2] = (rxbuf[4] << 8) + rxbuf[5];
/*added on 25th April 12*/
val[3] = (rxbuf[6] << 8) + rxbuf[7];
val[4] = (rxbuf[8] << 8) + rxbuf[9];
val[5] = (rxbuf[10] << 8) + rxbuf[11];
val[6] = (rxbuf[12] << 8) + rxbuf[13];
chprintf((BaseChannel *)&SD1, " MPU values are:");
j = 0;
for(i=0;i<7;i++){
//chprintf((BaseChannel *)&SD1, " \t%x \t%x", rxbuf[j], rxbuf[j+1]);
chprintf((BaseChannel *)&SD1, "\t%d ", val[i]);
j = j+2;
}
chprintf((BaseChannel *)&SD1, "\r\n");
chThdSleepMilliseconds(100);
}
Any idea what am I doing wrong?
hopefully with this one I will be able to use the full acceleration options.