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#include "sensor.hpp"
#include "sensor/registers.hpp"
Sensor::Sensor(uint8_t address, TwoWire wire, SerialStream sout,
unsigned int throttle_time)
: _wire(wire),
_sout(sout),
_address(address),
_throttle_enabled(true),
_throttle_time(throttle_time),
_last_time(0),
_status(SensorStatus::OK),
_accel_to_g_force(RAW_TO_G_FACTOR),
_ang_rate_to_dps(RAW_TO_DPS_FACTOR)
{
}
bool Sensor::begin() noexcept
{
_wire.begin();
if (isConnected())
{
_wire.beginTransmission(_address);
_wire.write(SensorRegisters::PWR_MGMT_1);
_wire.write(SENSOR_WAKEUP);
return (_wire.endTransmission() == 0);
}
return false;
}
bool Sensor::isConnected() noexcept
{
_wire.beginTransmission(_address);
return (_wire.endTransmission() == 0);
}
bool Sensor::read() noexcept
{
auto now = time_now();
if (_throttle_enabled && now.diff(_last_time).millisecs() < _throttle_time)
{
_status = SensorStatus::THROTTLED;
return false;
}
_wire.beginTransmission(_address);
_wire.write(SensorRegisters::ACCEL_XOUT_H);
if (_wire.endTransmission() != 0U)
{
_status = SensorStatus::ERR_WRITE;
return false;
}
uint8_t response_length = _wire.requestFrom(_address, SensorRegisters::SELF_TEST_Y);
const uint8_t self_test_success = 14U;
if (response_length != self_test_success)
{
_status = SensorStatus::ERR_READ;
return false;
}
// Accelerometer
_accel_raw_x = _readHighLow();
_accel_raw_y = _readHighLow();
_accel_raw_z = _readHighLow();
_sout << "\nAccel raw x: " << _accel_raw_x << "\n"
<< "Accel raw y: " << _accel_raw_y << "\n"
<< "Accel raw z: " << _accel_raw_z << "\n"
<< endl;
// Gyroscope
_gyro_raw_x = _readHighLow();
_gyro_raw_y = _readHighLow();
_gyro_raw_z = _readHighLow();
_sout << "\nGyro raw x: " << _gyro_raw_x << "\n"
<< "Gyro raw y: " << _gyro_raw_y << "\n"
<< "Gyro raw z: " << _gyro_raw_z << "\n"
<< endl;
// Duration interval
now.update();
auto duration = now.diff(_last_time).secs();
_last_time = now;
// Convert raw acceleration to g:s (g-force)
_accel_raw_x *= _accel_to_g_force;
_accel_raw_y *= _accel_to_g_force;
_accel_raw_z *= _accel_to_g_force;
_sout << "\nAccel raw x g:s: " << _accel_raw_x << "\n"
<< "Accel raw y g:s: " << _accel_raw_y << "\n"
<< "Accel raw z g:s: " << _accel_raw_z << "\n"
<< endl;
// Error correct raw acceleration
_accel_raw_x += accel_cal_x;
_accel_raw_y += accel_cal_y;
_accel_raw_z += accel_cal_z;
_sout << "\nAccel raw x correct: " << _accel_raw_x << "\n"
<< "Accel raw y correct: " << _accel_raw_y << "\n"
<< "Accel raw z correct: " << _accel_raw_z << "\n"
<< endl;
// Prepare for Pitch Roll Yaw
auto accel_y_pow_two = pow(_accel_raw_y, 2);
auto accel_z_pow_two = pow(_accel_raw_z, 2);
_accel_x = atan2(_accel_raw_y, _accel_raw_z) * ONE_EIGHTY / PI;
_accel_y =
atan2(-_accel_raw_x, sqrt(accel_y_pow_two + accel_z_pow_two)) * ONE_EIGHTY / PI;
/*
_accel_x =
atan(_accel_raw_y / sqrt(accel_x_pow_two + accel_z_pow_two)) * RAD_TO_DEGREES;
_accel_y = atan(-1.0 * _accel_raw_x / sqrt(accel_y_pow_two + accel_z_pow_two)) *
RAD_TO_DEGREES;
*/
// Convert raw Gyro to degrees/s
_gyro_raw_x *= _ang_rate_to_dps;
_gyro_raw_y *= _ang_rate_to_dps;
_gyro_raw_z *= _ang_rate_to_dps;
_sout << "\nGyro raw x dps: " << _gyro_raw_x << "\n"
<< "Gyro raw y dps: " << _gyro_raw_y << "\n"
<< "Gyro raw z dps: " << _gyro_raw_z << "\n"
<< endl;
// Error correct raw gyro measurements.
_gyro_raw_x += gyro_cal_x;
_gyro_raw_y += gyro_cal_y;
_gyro_raw_z += gyro_cal_z;
_sout << "\nGyro raw x correct: " << _gyro_raw_x << "\n"
<< "Gyro raw y correct: " << _gyro_raw_y << "\n"
<< "Gyro raw z correct: " << _gyro_raw_z << "\n"
<< endl;
_gyro_x += _gyro_raw_x * duration;
_gyro_y += _gyro_raw_y * duration;
_gyro_z += _gyro_raw_z * duration;
_sout << "\nGyro raw x w/o time: " << _gyro_raw_x << "\n"
<< "Gyro raw y w/o time: " << _gyro_raw_y << "\n"
<< "Gyro raw z w/o time: " << _gyro_raw_z << "\n"
<< endl;
const float gyro_balance = 0.96F;
const float accel_balance = 0.04F;
_pitch = gyro_balance * _gyro_y + accel_balance * _accel_y;
_roll = gyro_balance * _gyro_x + accel_balance * _accel_x;
_yaw = _gyro_z;
return true;
}
bool Sensor::setAccelSensitivity(uint8_t sensitivity) noexcept
{
if (sensitivity > 3)
{
sensitivity = 3;
}
_accel_sensitivity = sensitivity;
auto accel_config = static_cast<int>(getRegister(SensorRegisters::ACCEL_CONFIG));
if (_status != SensorStatus::OK)
{
return false;
}
// No need to write same value
if (((accel_config >> 3) & 3) != _accel_sensitivity)
{
const uint8_t magic = 0xE7U;
accel_config &= magic;
accel_config |= (_accel_sensitivity << 3U);
if (!setRegister(SensorRegisters::ACCEL_CONFIG,
static_cast<uint8_t>(accel_config)))
{
return false;
}
}
// Calculate conversion factor.
_accel_to_g_force = (1 << _accel_sensitivity) * RAW_TO_G_FACTOR;
return true;
}
bool Sensor::setGyroSensitivity(uint8_t sensitivity) noexcept
{
if (sensitivity > 3)
{
sensitivity = 3;
}
_gyro_sensitivity = sensitivity;
auto gyro_config = static_cast<int>(getRegister(SensorRegisters::GYRO_CONFIG));
if (_status != SensorStatus::OK)
{
return false;
}
// No need to write same value
if (((gyro_config >> 3) & 3) != _gyro_sensitivity)
{
const uint8_t magic = 0xE7U;
gyro_config &= magic;
gyro_config |= (_gyro_sensitivity << 3U);
if (!setRegister(SensorRegisters::GYRO_CONFIG, static_cast<uint8_t>(gyro_config)))
{
return false;
}
}
_ang_rate_to_dps = (1 << _gyro_sensitivity) * RAW_TO_DPS_FACTOR;
return true;
}
double Sensor::getAccelX() const noexcept
{
return _accel_raw_x;
}
double Sensor::getAccelY() const noexcept
{
return _accel_raw_y;
}
double Sensor::getAccelZ() const noexcept
{
return _accel_raw_z;
}
double Sensor::getAngleX() const noexcept
{
return _accel_x;
}
double Sensor::getAngleY() const noexcept
{
return _accel_y;
}
double Sensor::getGyroX() const noexcept
{
return _gyro_raw_x;
}
double Sensor::getGyroY() const noexcept
{
return _gyro_raw_y;
}
double Sensor::getGyroZ() const noexcept
{
return _gyro_raw_z;
}
double Sensor::getPitch() const noexcept
{
return _pitch;
}
double Sensor::getRoll() const noexcept
{
return _roll;
}
bool Sensor::setRegister(uint8_t reg, uint8_t value) noexcept
{
_wire.beginTransmission(_address);
_wire.write(reg);
_wire.write(value);
if (_wire.endTransmission() != 0)
{
_status = SensorStatus::ERR_WRITE;
return false;
}
return true;
}
uint8_t Sensor::getRegister(uint8_t reg) noexcept
{
_wire.beginTransmission(_address);
_wire.write(reg);
if (_wire.endTransmission() != 0U)
{
_status = SensorStatus::ERR_WRITE;
return 0U;
}
uint8_t response_length = _wire.requestFrom(_address, 1U);
if (response_length != 1U)
{
_status = SensorStatus::ERR_READ;
return 0U;
}
return static_cast<uint8_t>(_wire.read());
}
SensorStatus Sensor::getStatus() noexcept
{
SensorStatus status = _status;
_status = SensorStatus::OK;
return status;
}
int16_t Sensor::_readHighLow() noexcept
{
const int16_t high = _wire.read();
const int16_t low = _wire.read();
const int8_t bits_in_byte = 8;
return high << bits_in_byte | low;
}
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