Solved
Tilt function with LSM6DS3 not showing the right values. Am i reading it wrong ?
Hi, it is possible that the LSM6DS3 may be obsolete but i really need some help in detecting
a tilt.
I have read the AN4650 application note and followed the instructions.
the tilt example setup is pretty simple.
// Tilt detection setup
//
//***************************************************************************//
void LSM6DS3::tiltDetect()
{
// embedded function Tilt detecton CTRL10_C - 00111000
writeRegister(LSM6DS3_ACC_GYRO_CTRL1_XL, 0x20); // turn on the accelerometer/ ODR_XL=26Hz
writeRegister(LSM6DS3_ACC_GYRO_CTRL10_C, 0x3C); // enable embedded functions
writeRegister(LSM6DS3_ACC_GYRO_TAP_CFG, 0x20); // enable tilt detection
writeRegister(LSM6DS3_ACC_GYRO_MD1_CFG, 0x02); // tilt detector interrupt driven to INT1 pin
writeRegister(LSM6DS3_ACC_GYRO_CTRL10_C, 0x38);
}and then assuming that i don't want to use INT1 and INT2,
I can check the value of TILT_IA bit of the FUNC_SRC register
which I implemented it like this
// Tilt detection check
//
//***************************************************************************//
uint8_t LSM6DS3::readTilt( void )
{
uint8_t output;
readRegister(&output, LSM6DS3_ACC_GYRO_FUNC_SRC);
return output;
}Alright, so now, to my understanding, I know readRegister function reads a byte
of the FUNC_SRC register(unless i'm wrong ??) which itself is also a byte but how do i get the value of
the 5'th bit [BIT5] which is TILT_IA from my reading ???
By the way, I'm using an arduino.
This is the readRegister function.
ignore the SPI_MODE section
//
// ReadRegister
//
// Parameters:
// *outputPointer -- Pass &variable (address of) to save read data to
// offset -- register to read
//
//****************************************************************************//
status_t LSM6DS3Core::readRegister(uint8_t* outputPointer, uint8_t offset) {
//Return value
uint8_t result = 0;
uint8_t numBytes = 1;
status_t returnError = IMU_SUCCESS;
switch (commInterface) {
case I2C_MODE:
Wire.beginTransmission(I2CAddress);
Wire.write(offset);
if( Wire.endTransmission() != 0 )
{
returnError = IMU_HW_ERROR;
}
Wire.requestFrom(I2CAddress, numBytes);
while ( Wire.available() ) // slave may send less than requested
{
result = Wire.read(); // receive a byte as a proper uint8_t
}
break;
case SPI_MODE:
// take the chip select low to select the device:
digitalWrite(chipSelectPin, LOW);
// send the device the register you want to read:
SPI.transfer(offset | 0x80); //Ored with "read request" bit
// send a value of 0 to read the first byte returned:
result = SPI.transfer(0x00);
// take the chip select high to de-select:
digitalWrite(chipSelectPin, HIGH);
if( result == 0xFF )
{
//we've recieved all ones, report
returnError = IMU_ALL_ONES_WARNING;
}
break;
default:
break;
}
*outputPointer = result;
return returnError;
}Kind regards,
Johnson