| 0,0 → 1,400 |
|---|
| #include <avr/io.h> |
| #include <avr/interrupt.h> |
| #include <avr/pgmspace.h> |
| #include <stdlib.h> |
| |
| #include "analog.h" |
| #include "configuration.h" |
| #include "attitude.h" |
| #include "sensors.h" |
| #include "printf_P.h" |
| #include "isqrt.h" |
| #include "twimaster.h" |
| |
| // for Delay functions |
| #include "timer0.h" |
| |
| // For reading and writing acc. meter offsets. |
| #include "eeprom.h" |
| |
| // For debugOut |
| #include "output.h" |
| |
| // set ADC enable & ADC Start Conversion & ADC Interrupt Enable bit |
| #define startADC() (ADCSRA |= (1<<ADEN)|(1<<ADSC)|(1<<ADIE)) |
| |
| const char* recal = ", recalibration needed."; |
| |
| volatile uint16_t ADSensorInputs[8]; |
| |
| |
| /* |
| * These 4 exported variables are zero-offset. The "PID" ones are used |
| * in the attitude control as rotation rates. The "ATT" ones are for |
| * integration to angles. |
| */ |
| int16_t gyro_PID[3]; |
| int16_t gyro_ATT[3]; |
| int16_t gyroD[3]; |
| int16_t gyroDWindow[3][GYRO_D_WINDOW_LENGTH]; |
| uint8_t gyroDWindowIdx = 0; |
| |
| /* |
| * Airspeed |
| */ |
| uint32_t airpressure; |
| uint16_t airspeedVelocity = 0; |
| int16_t airpressureWindow[AIRPRESSURE_WINDOW_LENGTH]; |
| uint8_t airpressureWindowIdx = 0; |
| |
| /* |
| * Offset values. These are the raw gyro and acc. meter sums when the copter is |
| * standing still. They are used for adjusting the gyro and acc. meter values |
| * to be centered on zero. |
| */ |
| sensorOffset_t gyroOffset; |
| uint16_t airpressureOffset; |
| |
| /* |
| * In the MK coordinate system, nose-down is positive and left-roll is positive. |
| * If a sensor is used in an orientation where one but not both of the axes has |
| * an opposite sign, PR_ORIENTATION_REVERSED is set to 1 (true). |
| * Transform: |
| * pitch <- pp*pitch + pr*roll |
| * roll <- rp*pitch + rr*roll |
| * Not reversed, GYRO_QUADRANT: |
| * 0: pp=1, pr=0, rp=0, rr=1 // 0 degrees |
| * 1: pp=1, pr=-1,rp=1, rr=1 // +45 degrees |
| * 2: pp=0, pr=-1,rp=1, rr=0 // +90 degrees |
| * 3: pp=-1,pr=-1,rp=1, rr=1 // +135 degrees |
| * 4: pp=-1,pr=0, rp=0, rr=-1 // +180 degrees |
| * 5: pp=-1,pr=1, rp=-1,rr=-1 // +225 degrees |
| * 6: pp=0, pr=1, rp=-1,rr=0 // +270 degrees |
| * 7: pp=1, pr=1, rp=-1,rr=1 // +315 degrees |
| * Reversed, GYRO_QUADRANT: |
| * 0: pp=-1,pr=0, rp=0, rr=1 // 0 degrees with pitch reversed |
| * 1: pp=-1,pr=-1,rp=-1,rr=1 // +45 degrees with pitch reversed |
| * 2: pp=0, pr=-1,rp=-1,rr=0 // +90 degrees with pitch reversed |
| * 3: pp=1, pr=-1,rp=-1,rr=1 // +135 degrees with pitch reversed |
| * 4: pp=1, pr=0, rp=0, rr=-1 // +180 degrees with pitch reversed |
| * 5: pp=1, pr=1, rp=1, rr=-1 // +225 degrees with pitch reversed |
| * 6: pp=0, pr=1, rp=1, rr=0 // +270 degrees with pitch reversed |
| * 7: pp=-1,pr=1, rp=1, rr=1 // +315 degrees with pitch reversed |
| */ |
| |
| void rotate(int16_t* result, uint8_t quadrant, uint8_t reversePR, uint8_t reverseYaw) { |
| static const int8_t rotationTab[] = {1,1,0,-1,-1,-1,0,1}; |
| // Pitch to Pitch part |
| int8_t xx = reversePR ? rotationTab[(quadrant+4)%8] : rotationTab[quadrant]; |
| // Roll to Pitch part |
| int8_t xy = rotationTab[(quadrant+2)%8]; |
| // Pitch to Roll part |
| int8_t yx = reversePR ? rotationTab[(quadrant+2)%8] : rotationTab[(quadrant+6)%8]; |
| // Roll to Roll part |
| int8_t yy = rotationTab[quadrant]; |
| |
| int16_t xIn = result[0]; |
| result[0] = xx*xIn + xy*result[1]; |
| result[1] = yx*xIn + yy*result[1]; |
| |
| if (quadrant & 1) { |
| // A rotation was used above, where the factors were too large by sqrt(2). |
| // So, we multiply by 2^n/sqt(2) and right shift n bits, as to divide by sqrt(2). |
| // A suitable value for n: Sample is 11 bits. After transformation it is the sum |
| // of 2 11 bit numbers, so 12 bits. We have 4 bits left... |
| result[0] = (result[0]*11) >> 4; |
| result[1] = (result[1]*11) >> 4; |
| } |
| |
| if (reverseYaw) |
| result[3] =-result[3]; |
| } |
| |
| /* |
| * Battery voltage, in units of: 1k/11k / 3V * 1024 = 31.03 per volt. |
| * That is divided by 3 below, for a final 10.34 per volt. |
| * So the initial value of 100 is for 9.7 volts. |
| */ |
| uint16_t UBat = 100; |
| |
| /* |
| * Control and status. |
| */ |
| volatile uint8_t sensorDataReady = ALL_DATA_READY; |
| |
| /* |
| * Experiment: Measuring vibration-induced sensor noise. |
| */ |
| uint16_t gyroNoisePeak[3]; |
| |
| volatile uint8_t adState; |
| volatile uint8_t adChannel; |
| |
| // ADC channels |
| #define AD_UBAT 6 |
| #define AD_AIRPRESSURE 7 |
| |
| /* |
| * Table of AD converter inputs for each state. |
| * The number of samples summed for each channel is equal to |
| * the number of times the channel appears in the array. |
| * The max. number of samples that can be taken in 2 ms is: |
| * 20e6 / 128 / 13 / (1/2e-3) = 24. Since the main control |
| * loop needs a little time between reading AD values and |
| * re-enabling ADC, the real limit is (how much?) lower. |
| * The acc. sensor is sampled even if not used - or installed |
| * at all. The cost is not significant. |
| */ |
| |
| const uint8_t channelsForStates[] PROGMEM = { |
| AD_AIRPRESSURE, |
| AD_UBAT, |
| AD_AIRPRESSURE, |
| AD_AIRPRESSURE, |
| AD_AIRPRESSURE, |
| }; |
| |
| // Feature removed. Could be reintroduced later - but should work for all gyro types then. |
| // uint8_t GyroDefectPitch = 0, GyroDefectRoll = 0, GyroDefectYaw = 0; |
| |
| void analog_init(void) { |
| uint8_t sreg = SREG; |
| // disable all interrupts before reconfiguration |
| cli(); |
| |
| // ADC0 ... ADC7 is connected to PortA pin 0 ... 7 |
| // DDRA = 0x00; |
| // PORTA = 0x00; |
| // Digital Input Disable Register 0 |
| // Disable digital input buffer for analog adc_channel pins |
| // DIDR0 = 0xFF; |
| // external reference, adjust data to the right |
| ADMUX &= ~((1<<REFS1)|(1<<REFS0)|(1<<ADLAR)); |
| // set muxer to ADC adc_channel 0 (0 to 7 is a valid choice) |
| ADMUX = (ADMUX & 0xE0); |
| //Set ADC Control and Status Register A |
| //Auto Trigger Enable, Prescaler Select Bits to Division Factor 128, i.e. ADC clock = SYSCKL/128 = 156.25 kHz |
| ADCSRA = (1<<ADPS2)|(1<<ADPS1)|(1<<ADPS0); |
| //Set ADC Control and Status Register B |
| //Trigger Source to Free Running Mode |
| ADCSRB &= ~((1<<ADTS2)|(1<<ADTS1)|(1<<ADTS0)); |
| |
| startAnalogConversionCycle(); |
| |
| // restore global interrupt flags |
| SREG = sreg; |
| } |
| |
| /* |
| * Here the axes of the sensor can be shuffled around. |
| */ |
| uint16_t rawGyroValue(uint8_t axis) { |
| return IMU3200SensorInputs[axis+1]; // skip temperature mesaurement in any case.. |
| } |
| |
| /* |
| uint16_t rawAccValue(uint8_t axis) { |
| return sensorInputs[AD_ACC_PITCH-axis]; |
| } |
| */ |
| |
| void measureNoise(const int16_t sensor, |
| volatile uint16_t* const noiseMeasurement, const uint8_t damping) { |
| if (sensor > (int16_t) (*noiseMeasurement)) { |
| *noiseMeasurement = sensor; |
| } else if (-sensor > (int16_t) (*noiseMeasurement)) { |
| *noiseMeasurement = -sensor; |
| } else if (*noiseMeasurement > damping) { |
| *noiseMeasurement -= damping; |
| } else { |
| *noiseMeasurement = 0; |
| } |
| } |
| |
| void startAnalogConversionCycle(void) { |
| sensorDataReady = 0; |
| |
| // Stop the sampling. Cycle is over. |
| for (uint8_t i = 0; i<8; i++) { |
| ADSensorInputs[i] = 0; |
| } |
| |
| adState = 0; |
| adChannel = AD_AIRPRESSURE; |
| ADMUX = (ADMUX & 0xE0) | adChannel; |
| startADC(); |
| twimaster_startCycle(); |
| } |
| |
| /***************************************************** |
| * Interrupt Service Routine for ADC |
| * Runs at 312.5 kHz or 3.2 �s. When all states are |
| * processed further conversions are stopped. |
| *****************************************************/ |
| ISR(ADC_vect) { |
| ADSensorInputs[adChannel] += ADC; |
| // set up for next state. |
| adState++; |
| if (adState < sizeof(channelsForStates)) { |
| adChannel = pgm_read_byte(&channelsForStates[adState]); |
| // set adc muxer to next adChannel |
| ADMUX = (ADMUX & 0xE0) | adChannel; |
| // after full cycle stop further interrupts |
| startADC(); |
| } else { |
| sensorDataReady |= ADC_DATA_READY; |
| // do not restart ADC converter. |
| } |
| } |
| |
| void analog_updateGyros(void) { |
| // for various filters... |
| int16_t tempOffsetGyro[3], tempGyro; |
| |
| for (uint8_t axis=0; axis<3; axis++) { |
| tempGyro = rawGyroValue(axis); |
| /* |
| * Process the gyro data for the PID controller. |
| */ |
| |
| // Saturation prevention was removed. No airplane rotates more than 2000 deg/s. |
| |
| // 2) Apply sign and offset, scale before filtering. |
| tempOffsetGyro[axis] = (tempGyro - gyroOffset.offsets[axis]); |
| } |
| |
| // 2.1: Transform axes. |
| rotate(tempOffsetGyro, IMUConfig.gyroQuadrant, IMUConfig.imuReversedFlags & IMU_REVERSE_GYRO_PR, IMUConfig.imuReversedFlags & IMU_REVERSE_GYRO_YAW); |
| |
| for (uint8_t axis=0; axis<3; axis++) { |
| // 3) Filter. |
| tempOffsetGyro[axis] = (gyro_PID[axis] * (IMUConfig.gyroPIDFilterConstant - 1) + tempOffsetGyro[axis]) / IMUConfig.gyroPIDFilterConstant; |
| |
| // 4) Measure noise. |
| measureNoise(tempOffsetGyro[axis], &gyroNoisePeak[axis], GYRO_NOISE_MEASUREMENT_DAMPING); |
| |
| // 5) Differential measurement. |
| // TODO: Examine effects of overruns here, they are quite possible. |
| int16_t diff = tempOffsetGyro[axis] - gyro_PID[axis]; |
| gyroD[axis] -= gyroDWindow[axis][gyroDWindowIdx]; |
| gyroD[axis] += diff; |
| gyroDWindow[axis][gyroDWindowIdx] = diff; |
| |
| // 6) Done. |
| gyro_PID[axis] = tempOffsetGyro[axis]; |
| |
| // Prepare tempOffsetGyro for next calculation below... |
| tempOffsetGyro[axis] = (rawGyroValue(axis) - gyroOffset.offsets[axis]); |
| } |
| |
| /* |
| * Now process the data for attitude angles. |
| */ |
| rotate(tempOffsetGyro, IMUConfig.gyroQuadrant, IMUConfig.imuReversedFlags & IMU_REVERSE_GYRO_PR, IMUConfig.imuReversedFlags & IMU_REVERSE_GYRO_YAW); |
| |
| // dampenGyroActivity(); |
| gyro_ATT[PITCH] = tempOffsetGyro[PITCH]; |
| gyro_ATT[ROLL] = tempOffsetGyro[ROLL]; |
| gyro_ATT[YAW] = tempOffsetGyro[YAW]; |
| |
| if (++gyroDWindowIdx >= IMUConfig.gyroDWindowLength) { |
| gyroDWindowIdx = 0; |
| } |
| } |
| |
| // probably wanna aim at 1/10 m/s/unit. |
| #define LOG_AIRSPEED_FACTOR 2 |
| |
| void analog_updateAirspeed(void) { |
| uint16_t rawAirpressure = ADSensorInputs[AD_AIRPRESSURE]; |
| int16_t temp = rawAirpressure - airpressureOffset; |
| airpressure -= airpressureWindow[airpressureWindowIdx]; |
| airpressure += temp; |
| airpressureWindow[airpressureWindowIdx] = temp; |
| airpressureWindowIdx++; |
| if (airpressureWindowIdx == AIRPRESSURE_WINDOW_LENGTH) { |
| airpressureWindowIdx = 0; |
| } |
| |
| if (temp<0) temp = 0; |
| airspeedVelocity = (staticParams.airspeedCorrection * isqrt32(airpressure)) >> LOG_AIRSPEED_FACTOR; |
| isFlying = (airspeedVelocity >= staticParams.isFlyingThreshold); |
| } |
| |
| void analog_updateBatteryVoltage(void) { |
| // Battery. The measured value is: (V * 1k/11k)/3v * 1024 = 31.03 counts per volt (max. measurable is 33v). |
| // This is divided by 3 --> 10.34 counts per volt. |
| UBat = (3 * UBat + ADSensorInputs[AD_UBAT] / 3) / 4; |
| } |
| |
| void analog_update(void) { |
| analog_updateGyros(); |
| // analog_updateAccelerometers(); |
| analog_updateAirspeed(); |
| analog_updateBatteryVoltage(); |
| #ifdef USE_MK3MAG |
| magneticHeading = volatileMagneticHeading; |
| #endif |
| } |
| |
| void analog_setNeutral() { |
| twimaster_setNeutral(); |
| |
| if (gyroOffset_readFromEEProm()) { |
| printf("gyro offsets invalid%s",recal); |
| gyroOffset.offsets[PITCH] = gyroOffset.offsets[ROLL] = 512 * GYRO_OVERSAMPLING; |
| gyroOffset.offsets[YAW] = 512 * GYRO_OVERSAMPLING; |
| } |
| |
| // Noise is relative to offset. So, reset noise measurements when changing offsets. |
| for (uint8_t i=PITCH; i<=YAW; i++) { |
| gyroNoisePeak[i] = 0; |
| gyroD[i] = 0; |
| for (uint8_t j=0; j<GYRO_D_WINDOW_LENGTH; j++) { |
| gyroDWindow[i][j] = 0; |
| } |
| } |
| |
| for (uint8_t i=0; i<AIRPRESSURE_WINDOW_LENGTH; i++) { |
| airpressureWindow[i] = 0; |
| } |
| |
| // Setting offset values has an influence in the analog.c ISR |
| // Therefore run measurement for 100ms to achive stable readings |
| delay_ms_with_adc_measurement(100, 0); |
| |
| // gyroActivity = 0; |
| } |
| |
| void analog_calibrate(void) { |
| #define OFFSET_CYCLES 64 |
| uint8_t i, axis; |
| int32_t offsets[4] = { 0, 0, 0, 0}; |
| |
| // determine gyro bias by averaging (requires that the copter does not rotate around any axis!) |
| for (i = 0; i < OFFSET_CYCLES; i++) { |
| delay_ms_with_adc_measurement(10, 1); |
| for (axis = PITCH; axis <= YAW; axis++) { |
| offsets[axis] += rawGyroValue(axis); |
| } |
| offsets[3] += ADSensorInputs[AD_AIRPRESSURE]; |
| } |
| |
| for (axis = PITCH; axis <= YAW; axis++) { |
| gyroOffset.offsets[axis] = (offsets[axis] + OFFSET_CYCLES / 2) / OFFSET_CYCLES; |
| int16_t min = (512-200) * GYRO_OVERSAMPLING; |
| int16_t max = (512+200) * GYRO_OVERSAMPLING; |
| if(gyroOffset.offsets[axis] < min || gyroOffset.offsets[axis] > max) |
| versionInfo.hardwareErrors[0] |= FC_ERROR0_GYRO_PITCH << axis; |
| } |
| |
| airpressureOffset = (offsets[3] + OFFSET_CYCLES / 2) / OFFSET_CYCLES; |
| int16_t min = 200; |
| int16_t max = (1024-200) * 2; |
| if(airpressureOffset < min || airpressureOffset > max) |
| versionInfo.hardwareErrors[0] |= FC_ERROR0_PRESSURE; |
| |
| gyroOffset_writeToEEProm(); |
| |
| startAnalogConversionCycle(); |
| } |