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2108 - 1
#ifndef _ANALOG_H
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#define _ANALOG_H
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#include <inttypes.h>
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#include "configuration.h"
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/*
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 About setting constants for different gyros:
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 Main parameters are positive directions and voltage/angular speed gain.
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 The "Positive direction" is the rotation direction around an axis where
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 the corresponding gyro outputs a voltage > the no-rotation voltage.
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 A gyro is considered, in this code, to be "forward" if its positive
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 direction is:
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 - Nose down for pitch
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 - Left hand side down for roll
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 - Clockwise seen from above for yaw.
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 Setting gyro gain correctly: All sensor measurements in analog.c take
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 place in a cycle, each cycle comprising all sensors. Some sensors are
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 sampled more than once (oversampled), and the results added.
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 In the H&I code, the results for pitch and roll are multiplied by 2 (FC1.0)
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 or 4 (other versions), offset to zero, low pass filtered and then assigned
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 to the "HiResXXXX" and "AdWertXXXXFilter" variables, where XXXX is nick or
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 roll. The factor 2 or 4 or whatever is called GYRO_FACTOR_PITCHROLL here.
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*/
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/*
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 GYRO_HW_FACTOR is the relation between rotation rate and ADCValue:
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 ADCValue [units] =
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 rotational speed [deg/s] *
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 gyro sensitivity [V / deg/s] *
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 amplifier gain [units] *
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 1024 [units] /
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 3V full range [V]
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 GYRO_HW_FACTOR is:
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 gyro sensitivity [V / deg/s] *
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 amplifier gain [units] *
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 1024 [units] /
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 3V full range [V]
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 Examples:
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 FC1.3 has 0.67 mV/deg/s gyros and amplifiers with a gain of 5.7:
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 GYRO_HW_FACTOR = 0.00067 V / deg / s * 5.7 * 1024 / 3V = 1.304 units/(deg/s).
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 FC2.0 has 6*(3/5) mV/deg/s gyros (they are ratiometric) and no amplifiers:
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 GYRO_HW_FACTOR = 0.006 V / deg / s * 1 * 1024 * 3V / (3V * 5V) = 1.2288 units/(deg/s).
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 My InvenSense copter has 2mV/deg/s gyros and no amplifiers:
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 GYRO_HW_FACTOR = 0.002 V / deg / s * 1 * 1024 / 3V = 0.6827 units/(deg/s)
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 (only about half as sensitive as V1.3. But it will take about twice the
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 rotation rate!)
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 GYRO_HW_FACTOR is given in the makefile.
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*/
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/*
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 * How many samples are added in one ADC loop, for pitch&roll and yaw,
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 * respectively. This is = the number of occurences of each channel in the
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 * channelsForStates array in analog.c.
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 */
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#define GYRO_OVERSAMPLING 4
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/*
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 * The product of the 3 above constants. This represents the expected change in ADC value sums for 1 deg/s of rotation rate.
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 */
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#define GYRO_RATE_FACTOR (GYRO_HW_FACTOR * GYRO_OVERSAMPLING)
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/*
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 * The value of gyro[PITCH/ROLL] for one deg/s = The hardware factor H * the number of samples * multiplier factor.
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 * Will be about 10 or so for InvenSense, and about 33 for ADXRS610.
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 */
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/*
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 * Gyro saturation prevention.
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 */
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// How far from the end of its range a gyro is considered near-saturated.
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#define SENSOR_MIN 32
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// Other end of the range (calculated)
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#define SENSOR_MAX (GYRO_OVERSAMPLING * 1023 - SENSOR_MIN)
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// Max. boost to add "virtually" to gyro signal at total saturation.
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#define EXTRAPOLATION_LIMIT 2500
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// Slope of the boost (calculated)
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#define EXTRAPOLATION_SLOPE (EXTRAPOLATION_LIMIT/SENSOR_MIN)
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/*
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 * This value is subtracted from the gyro noise measurement in each iteration,
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 * making it return towards zero.
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 */
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#define GYRO_NOISE_MEASUREMENT_DAMPING 5
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#define PITCH 0
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#define ROLL 1
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#define YAW 2
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//#define Z 2
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/*
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 * The values that this module outputs
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 * These first 2 exported arrays are zero-offset. The "PID" ones are used
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 * in the attitude control as rotation rates. The "ATT" ones are for
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 * integration to angles. For the same axis, the PID and ATT variables
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 * generally have about the same values. There are just some differences
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 * in filtering, and when a gyro becomes near saturated.
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 * Maybe this distinction is not really necessary.
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 */
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extern int16_t gyro_PID[3];
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extern int16_t gyro_ATT[3];
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extern int16_t gyroD[3];
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#define GYRO_D_WINDOW_LENGTH 16
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extern uint16_t UBat;
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extern uint16_t airspeedVelocity;
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// 1:11 voltage divider, 1024 counts per 3V, and result is divided by 3.
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#define UBAT_AT_5V (int16_t)((5.0 * (1.0/11.0)) * 1024 / (3.0 * 3))
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extern sensorOffset_t gyroOffset;
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extern uint16_t airpressureOffset;
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/*
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 * This is not really for external use - but the ENC-03 gyro modules needs it.
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 */
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//extern volatile int16_t rawGyroSum[3];
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/*
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 * The acceleration values that this module outputs. They are zero based.
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 */
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//extern int16_t acc[3];
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//extern int16_t filteredAcc[3];
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// extern volatile int32_t stronglyFilteredAcc[3];
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/*
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 * Diagnostics: Gyro noise level because of motor vibrations. The variables
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 * only really reflect the noise level when the copter stands still but with
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 * its motors running.
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 */
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extern uint16_t gyroNoisePeak[3];
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/*
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 * Air pressure.
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 * The sensor has a sensitivity of 45 mV/kPa.
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 * An approximate p(h) formula is = p(h[m])[kPa] = p_0 - 11.95 * 10^-3 * h
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 * p(h[m])[kPa] = 101.3 - 11.95 * 10^-3 * h
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 * 11.95 * 10^-3 * h = 101.3 - p[kPa]
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 * h = (101.3 - p[kPa])/0.01195
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 * That is: dV = -45 mV * 11.95 * 10^-3 dh = -0.53775 mV / m.
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 * That is, with 38.02 * 1.024 / 3 steps per mV: -7 steps / m
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Display pressures
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4165 mV-->1084.7
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4090 mV-->1602.4   517.7
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3877 mV-->3107.8  1503.4
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4165 mV-->1419.1
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3503 mV-->208.1
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Diff.:   1211.0
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Calculated  Vout = 5V(.009P-0.095) --> 5V .009P = Vout + 5V 0.095 --> P = (Vout + 5V 0.095)/(5V 0.009)
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4165 mV = 5V(0.009P-0.095)  P = 103.11 kPa  h = -151.4m
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4090 mV = 5V(0.009P-0.095)  P = 101.44 kPa  h = -11.7m   139.7m
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3877 mV = 5V(0.009P-0.095)  P = 96.7   kPa  h = 385m     396.7m
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4165 mV = 5V(0.009P-0.095)  P = 103.11 kPa  h = -151.4m
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3503 mV = 5V(0.009P-0.095)  P = 88.4   kPa  h = 384m  Diff: 1079.5m
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Pressure at sea level: 101.3 kPa. voltage: 5V * (0.009P-0.095) = 4.0835V
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This is OCR2 = 143.15 at 1.5V in --> simple pressure =
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*/
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#define AIRPRESSURE_WINDOW_LENGTH 32
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extern uint16_t airspeedVelocity;
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/*
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 * Flag: Interrupt handler has done all A/D conversion and processing.
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 */
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#define ADC_DATA_READY 1
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#define TWI_DATA_READY 2
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#define ALL_DATA_READY (ADC_DATA_READY+TWI_DATA_READY)
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extern volatile uint8_t sensorDataReady;
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void analog_init(void);
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/*
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 * This is really only for use for the ENC-03 code module, which needs to get the raw value
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 * for its calibration. The raw value should not be used for anything else.
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 */
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//int16_t rawGyroValue(uint8_t axis);
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/*
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 * Start the conversion cycle. It will stop automatically.
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 */
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void startAnalogConversionCycle(void);
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/*
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 * Process the sensor data to update the exported variables. Must be called after each measurement cycle and before the data is used.
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 */
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void analog_update(void);
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/*
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 * Read gyro and acc.meter calibration from EEPROM.
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 */
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void analog_setNeutral(void);
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/*
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 * Zero-offset gyros and write the calibration data to EEPROM.
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 */
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void analog_calibrate(void);
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#endif //_ANALOG_H