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1612 dongfang 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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 * How much low pass filtering to apply for gyro_PID.
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 * 0=illegal, 1=no filtering, 2=50% last value + 50% new value, 3=67% last value + 33 % new value etc...
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 * Temporarily replaced by userparam-configurable variable.
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 */
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// #define GYROS_PID_FILTER 1
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13
/*
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 * How much low pass filtering to apply for gyro_ATT.
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 * 0=illegal, 1=no filtering, 2=50% last value + 50% new value, 3=67% last value + 33 % new value etc...
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 * Temporarily replaced by userparam-configurable variable.
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 */
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// #define GYROS_ATT_FILTER 1
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// Temporarily replaced by userparam-configurable variable.
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// #define ACC_FILTER 4
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23
/*
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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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 Declare the GYRO_REVERSE_YAW, GYRO_REVERSE_ROLL and
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 GYRO_REVERSE_PITCH #define's if the respective gyros are reverse.
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36
 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 ones, and the results added. The pitch and roll gyros
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 are sampled 4 times and the yaw gyro 2 times in the original H&I V0.74
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 code.
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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.
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 So:
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47
 gyro = V * (ADCValue1 + ADCValue2 + ADCValue3 + ADCValue4),
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 where V is 2 for FC1.0 and 4 for all others.
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50
 Assuming constant ADCValue, in the H&I code:
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 gyro = I * ADCValue.
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 where I is 8 for FC1.0 and 16 for all others.
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 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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 or: H is the number of steps the ADC value changes with,
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 for a 1 deg/s change in rotational velocity:
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 H = ADCValue [units] / rotation rate [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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 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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 H = 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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 H = 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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 H = 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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 All together: gyro = I * H * rotation rate [units / (deg/s)].
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 */
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/*
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 * A factor that the raw gyro values are multiplied by,
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 * before being filtered and passed to the attitude module.
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 * A value of 1 would cause a little bit of loss of precision in the
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 * filtering (on the other hand the values are so noisy in flight that
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 * it will not really matter - but when testing on the desk it might be
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 * noticeable). 4 is fine for the default filtering.
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 * Experiment: Set it to 1.
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 */
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#define GYRO_FACTOR_PITCHROLL 1
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/*
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 * How many samples are summed 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_SUMMATION_FACTOR_PITCHROLL 4
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#define GYRO_SUMMATION_FACTOR_YAW 2
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#define ACC_SUMMATION_FACTOR_PITCHROLL 2
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#define ACC_SUMMATION_FACTOR_Z 1
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/*
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 Integration:
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 The HiResXXXX values are divided by 8 (in H&I firmware) before integration.
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 In the Killagreg rewrite of the H&I firmware, the factor 8 is called
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 HIRES_GYRO_AMPLIFY. In this code, it is called HIRES_GYRO_INTEGRATION_FACTOR,
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 and care has been taken that all other constants (gyro to degree factor, and
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 180 degree flip-over detection limits) are corrected to it. Because the
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 division by the constant takes place in the flight attitude code, the
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 constant is there.
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 The control loop executes every 2ms, and for each iteration
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 gyro_ATT[PITCH/ROLL] is added to gyroIntegral[PITCH/ROLL].
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 Assuming a constant rotation rate v and a zero initial gyroIntegral
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 (for this explanation), we get:
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 gyroIntegral =
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 N * gyro / HIRES_GYRO_INTEGRATION_FACTOR =
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 N * I * H * v / HIRES_GYRO_INTEGRATION_FACTOR
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 where N is the number of summations; N = t/2ms.
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 For one degree of rotation: t*v = 1:
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 gyroIntegralXXXX = t/2ms * I * H * 1/t = INTEGRATION_FREQUENCY * I * H / HIRES_GYRO_INTEGRATION_FACTOR.
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 This number (INTEGRATION_FREQUENCY * I * H) is the integral-to-degree factor.
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134
 Examples:
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 FC1.3: I=2, H=1.304, HIRES_GYRO_INTEGRATION_FACTOR=8 --> integralDegreeFactor = 1304
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 FC2.0: I=2, H=2.048, HIRES_GYRO_INTEGRATION_FACTOR=13 --> integralDegreeFactor = 1260
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 My InvenSense copter: HIRES_GYRO_INTEGRATION_FACTOR=4, H=0.6827 --> integralDegreeFactor = 1365
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 */
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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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#define GYRO_RATE_FACTOR_PITCHROLL (GYRO_HW_FACTOR * GYRO_SUMMATION_FACTOR_PITCHROLL * GYRO_FACTOR_PITCHROLL)
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#define GYRO_RATE_FACTOR_YAW (GYRO_HW_FACTOR * GYRO_SUMMATION_FACTOR_YAW)
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/*
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 * Gyro saturation prevention.
149
 */
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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_PITCHROLL 32
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// Other end of the range (calculated)
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#define SENSOR_MAX_PITCHROLL (GYRO_SUMMATION_FACTOR_PITCHROLL * 1023 - SENSOR_MIN_PITCHROLL)
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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_PITCHROLL)
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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 volatile int16_t gyro_PID[2];
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extern volatile int16_t gyro_ATT[2];
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extern volatile int16_t gyroD[2];
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extern volatile int16_t yawGyro;
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extern volatile uint16_t ADCycleCount;
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extern volatile int16_t UBat;
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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 sensorOffset_t accOffset;
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extern sensorOffset_t gyroAmplifierOffset;
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/*
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 * This is not really for external use - but the ENC-03 gyro modules needs it.
194
 */
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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 volatile int16_t acc[3];
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extern volatile 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 volatile uint16_t gyroNoisePeak[3];
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extern volatile uint16_t accNoisePeak[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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227
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_SUMMATION_FACTOR 14
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#define AIRPRESSURE_FILTER 8
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// Minimum A/D value before a range change is performed.
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#define MIN_RAWPRESSURE (200 * 2)
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// Maximum A/D value before a range change is performed.
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#define MAX_RAWPRESSURE (1023 * 2 - MIN_RAWPRESSURE)
248
 
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#define MIN_RANGES_EXTRAPOLATION 15
250
#define MAX_RANGES_EXTRAPOLATION 240
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252
#define PRESSURE_EXTRAPOLATION_COEFF 25L
253
#define AUTORANGE_WAIT_FACTOR 1
254
 
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#define ABS_ALTITUDE_OFFSET 108205
256
 
1775 - 257
extern volatile uint16_t simpleAirPressure;
258
/*
259
 * At saturation, the filteredAirPressure may actually be (simulated) negative.
260
 */
261
extern volatile int32_t filteredAirPressure;
262
 
263
/*
1612 dongfang 264
 * Flag: Interrupt handler has done all A/D conversion and processing.
265
 */
266
extern volatile uint8_t analogDataReady;
267
 
268
void analog_init(void);
269
 
1952 - 270
/*
271
 * Start the conversion cycle. It will stop automatically.
272
 */
273
void startAnalogConversionCycle(void);
1612 dongfang 274
 
1952 - 275
/*
276
 * Process the sensor data to update the exported variables. Must be called after each measurement cycle and before the data is used.
277
 */
1955 - 278
void analog_update(void);
1612 dongfang 279
 
280
/*
1961 - 281
 * Read gyro and acc.meter calibration from EEPROM.
1612 dongfang 282
 */
1961 - 283
void analog_setNeutral(void);
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285
/*
1961 - 286
 * Zero-offset gyros and write the calibration data to EEPROM.
1612 dongfang 287
 */
1961 - 288
void analog_calibrateGyros(void);
289
 
290
/*
291
 * Zero-offset accelerometers and write the calibration data to EEPROM.
292
 */
1612 dongfang 293
void analog_calibrateAcc(void);
294
#endif //_ANALOG_H