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1612 | dongfang | 1 | #ifndef _ANALOG_H |
2 | #define _ANALOG_H |
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3 | #include <inttypes.h> |
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1965 | - | 4 | #include "configuration.h" |
1612 | dongfang | 5 | |
6 | /* |
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1645 | - | 7 | * How much low pass filtering to apply for gyro_PID. |
1612 | dongfang | 8 | * 0=illegal, 1=no filtering, 2=50% last value + 50% new value, 3=67% last value + 33 % new value etc... |
9 | * Temporarily replaced by userparam-configurable variable. |
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10 | */ |
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1646 | - | 11 | // #define GYROS_PID_FILTER 1 |
1612 | dongfang | 12 | |
13 | /* |
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1645 | - | 14 | * How much low pass filtering to apply for gyro_ATT. |
1612 | dongfang | 15 | * 0=illegal, 1=no filtering, 2=50% last value + 50% new value, 3=67% last value + 33 % new value etc... |
16 | * Temporarily replaced by userparam-configurable variable. |
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17 | */ |
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1646 | - | 18 | // #define GYROS_ATT_FILTER 1 |
1612 | dongfang | 19 | // Temporarily replaced by userparam-configurable variable. |
1646 | - | 20 | // #define ACC_FILTER 4 |
1612 | dongfang | 21 | |
22 | /* |
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1821 | - | 23 | About setting constants for different gyros: |
24 | Main parameters are positive directions and voltage/angular speed gain. |
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25 | The "Positive direction" is the rotation direction around an axis where |
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26 | the corresponding gyro outputs a voltage > the no-rotation voltage. |
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27 | A gyro is considered, in this code, to be "forward" if its positive |
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28 | direction is: |
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29 | - Nose down for pitch |
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30 | - Left hand side down for roll |
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31 | - Clockwise seen from above for yaw. |
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32 | Declare the GYRO_REVERSE_YAW, GYRO_REVERSE_ROLL and |
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33 | GYRO_REVERSE_PITCH #define's if the respective gyros are reverse. |
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34 | |||
35 | Setting gyro gain correctly: All sensor measurements in analog.c take |
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36 | place in a cycle, each cycle comprising all sensors. Some sensors are |
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37 | sampled more than ones, and the results added. The pitch and roll gyros |
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38 | are sampled 4 times and the yaw gyro 2 times in the original H&I V0.74 |
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39 | code. |
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40 | In the H&I code, the results for pitch and roll are multiplied by 2 (FC1.0) |
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41 | or 4 (other versions), offset to zero, low pass filtered and then assigned |
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42 | to the "HiResXXXX" and "AdWertXXXXFilter" variables, where XXXX is nick or |
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43 | roll. |
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44 | So: |
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45 | |||
46 | gyro = V * (ADCValue1 + ADCValue2 + ADCValue3 + ADCValue4), |
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47 | where V is 2 for FC1.0 and 4 for all others. |
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48 | |||
49 | Assuming constant ADCValue, in the H&I code: |
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1612 | dongfang | 50 | |
1821 | - | 51 | gyro = I * ADCValue. |
1612 | dongfang | 52 | |
1821 | - | 53 | where I is 8 for FC1.0 and 16 for all others. |
1612 | dongfang | 54 | |
1821 | - | 55 | The relation between rotation rate and ADCValue: |
56 | ADCValue [units] = |
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57 | rotational speed [deg/s] * |
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58 | gyro sensitivity [V / deg/s] * |
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59 | amplifier gain [units] * |
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60 | 1024 [units] / |
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61 | 3V full range [V] |
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1612 | dongfang | 62 | |
1821 | - | 63 | or: H is the number of steps the ADC value changes with, |
64 | for a 1 deg/s change in rotational velocity: |
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65 | H = ADCValue [units] / rotation rate [deg/s] = |
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66 | gyro sensitivity [V / deg/s] * |
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67 | amplifier gain [units] * |
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68 | 1024 [units] / |
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69 | 3V full range [V] |
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1612 | dongfang | 70 | |
1821 | - | 71 | Examples: |
72 | FC1.3 has 0.67 mV/deg/s gyros and amplifiers with a gain of 5.7: |
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73 | H = 0.00067 V / deg / s * 5.7 * 1024 / 3V = 1.304 units/(deg/s). |
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74 | FC2.0 has 6*(3/5) mV/deg/s gyros (they are ratiometric) and no amplifiers: |
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75 | H = 0.006 V / deg / s * 1 * 1024 * 3V / (3V * 5V) = 1.2288 units/(deg/s). |
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76 | My InvenSense copter has 2mV/deg/s gyros and no amplifiers: |
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77 | H = 0.002 V / deg / s * 1 * 1024 / 3V = 0.6827 units/(deg/s) |
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78 | (only about half as sensitive as V1.3. But it will take about twice the |
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79 | rotation rate!) |
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1612 | dongfang | 80 | |
1821 | - | 81 | All together: gyro = I * H * rotation rate [units / (deg/s)]. |
82 | */ |
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1612 | dongfang | 83 | |
84 | /* |
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85 | * A factor that the raw gyro values are multiplied by, |
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1645 | - | 86 | * before being filtered and passed to the attitude module. |
1612 | dongfang | 87 | * A value of 1 would cause a little bit of loss of precision in the |
88 | * filtering (on the other hand the values are so noisy in flight that |
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89 | * it will not really matter - but when testing on the desk it might be |
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90 | * noticeable). 4 is fine for the default filtering. |
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1645 | - | 91 | * Experiment: Set it to 1. |
1612 | dongfang | 92 | */ |
1874 | - | 93 | #define GYRO_FACTOR_PITCHROLL 1 |
1612 | dongfang | 94 | |
95 | /* |
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96 | * How many samples are summed in one ADC loop, for pitch&roll and yaw, |
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97 | * respectively. This is = the number of occurences of each channel in the |
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98 | * channelsForStates array in analog.c. |
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99 | */ |
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100 | #define GYRO_SUMMATION_FACTOR_PITCHROLL 4 |
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101 | #define GYRO_SUMMATION_FACTOR_YAW 2 |
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102 | |||
1646 | - | 103 | #define ACC_SUMMATION_FACTOR_PITCHROLL 2 |
104 | #define ACC_SUMMATION_FACTOR_Z 1 |
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105 | |||
1612 | dongfang | 106 | /* |
1821 | - | 107 | Integration: |
108 | The HiResXXXX values are divided by 8 (in H&I firmware) before integration. |
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109 | In the Killagreg rewrite of the H&I firmware, the factor 8 is called |
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110 | HIRES_GYRO_AMPLIFY. In this code, it is called HIRES_GYRO_INTEGRATION_FACTOR, |
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111 | and care has been taken that all other constants (gyro to degree factor, and |
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112 | 180 degree flip-over detection limits) are corrected to it. Because the |
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113 | division by the constant takes place in the flight attitude code, the |
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114 | constant is there. |
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1612 | dongfang | 115 | |
1821 | - | 116 | The control loop executes every 2ms, and for each iteration |
117 | gyro_ATT[PITCH/ROLL] is added to gyroIntegral[PITCH/ROLL]. |
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118 | Assuming a constant rotation rate v and a zero initial gyroIntegral |
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119 | (for this explanation), we get: |
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1612 | dongfang | 120 | |
1821 | - | 121 | gyroIntegral = |
122 | N * gyro / HIRES_GYRO_INTEGRATION_FACTOR = |
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123 | N * I * H * v / HIRES_GYRO_INTEGRATION_FACTOR |
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1612 | dongfang | 124 | |
1821 | - | 125 | where N is the number of summations; N = t/2ms. |
1612 | dongfang | 126 | |
1821 | - | 127 | For one degree of rotation: t*v = 1: |
1612 | dongfang | 128 | |
1821 | - | 129 | gyroIntegralXXXX = t/2ms * I * H * 1/t = INTEGRATION_FREQUENCY * I * H / HIRES_GYRO_INTEGRATION_FACTOR. |
1612 | dongfang | 130 | |
1821 | - | 131 | This number (INTEGRATION_FREQUENCY * I * H) is the integral-to-degree factor. |
132 | |||
133 | Examples: |
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134 | FC1.3: I=2, H=1.304, HIRES_GYRO_INTEGRATION_FACTOR=8 --> integralDegreeFactor = 1304 |
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135 | FC2.0: I=2, H=2.048, HIRES_GYRO_INTEGRATION_FACTOR=13 --> integralDegreeFactor = 1260 |
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136 | My InvenSense copter: HIRES_GYRO_INTEGRATION_FACTOR=4, H=0.6827 --> integralDegreeFactor = 1365 |
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137 | */ |
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138 | |||
1612 | dongfang | 139 | /* |
1645 | - | 140 | * The value of gyro[PITCH/ROLL] for one deg/s = The hardware factor H * the number of samples * multiplier factor. |
1612 | dongfang | 141 | * Will be about 10 or so for InvenSense, and about 33 for ADXRS610. |
142 | */ |
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143 | #define GYRO_RATE_FACTOR_PITCHROLL (GYRO_HW_FACTOR * GYRO_SUMMATION_FACTOR_PITCHROLL * GYRO_FACTOR_PITCHROLL) |
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144 | #define GYRO_RATE_FACTOR_YAW (GYRO_HW_FACTOR * GYRO_SUMMATION_FACTOR_YAW) |
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145 | |||
146 | /* |
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1645 | - | 147 | * Gyro saturation prevention. |
148 | */ |
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149 | // How far from the end of its range a gyro is considered near-saturated. |
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150 | #define SENSOR_MIN_PITCHROLL 32 |
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151 | // Other end of the range (calculated) |
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152 | #define SENSOR_MAX_PITCHROLL (GYRO_SUMMATION_FACTOR_PITCHROLL * 1023 - SENSOR_MIN_PITCHROLL) |
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153 | // Max. boost to add "virtually" to gyro signal at total saturation. |
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154 | #define EXTRAPOLATION_LIMIT 2500 |
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155 | // Slope of the boost (calculated) |
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156 | #define EXTRAPOLATION_SLOPE (EXTRAPOLATION_LIMIT/SENSOR_MIN_PITCHROLL) |
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157 | |||
158 | /* |
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1612 | dongfang | 159 | * This value is subtracted from the gyro noise measurement in each iteration, |
160 | * making it return towards zero. |
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161 | */ |
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162 | #define GYRO_NOISE_MEASUREMENT_DAMPING 5 |
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163 | |||
1645 | - | 164 | #define PITCH 0 |
165 | #define ROLL 1 |
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1646 | - | 166 | #define YAW 2 |
167 | #define Z 2 |
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1612 | dongfang | 168 | /* |
169 | * The values that this module outputs |
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1645 | - | 170 | * These first 2 exported arrays are zero-offset. The "PID" ones are used |
171 | * in the attitude control as rotation rates. The "ATT" ones are for |
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172 | * integration to angles. For the same axis, the PID and ATT variables |
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173 | * generally have about the same values. There are just some differences |
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174 | * in filtering, and when a gyro becomes near saturated. |
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175 | * Maybe this distinction is not really necessary. |
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1612 | dongfang | 176 | */ |
2015 | - | 177 | extern int16_t gyro_PID[2]; |
178 | extern int16_t gyro_ATT[2]; |
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179 | extern int16_t gyroD[2]; |
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180 | extern int16_t yawGyro; |
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1612 | dongfang | 181 | extern volatile uint16_t ADCycleCount; |
2015 | - | 182 | extern int16_t UBat; |
1612 | dongfang | 183 | |
1775 | - | 184 | // 1:11 voltage divider, 1024 counts per 3V, and result is divided by 3. |
1869 | - | 185 | #define UBAT_AT_5V (int16_t)((5.0 * (1.0/11.0)) * 1024 / (3.0 * 3)) |
1775 | - | 186 | |
1969 | - | 187 | extern sensorOffset_t gyroOffset; |
188 | extern sensorOffset_t accOffset; |
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189 | extern sensorOffset_t gyroAmplifierOffset; |
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1960 | - | 190 | |
1612 | dongfang | 191 | /* |
192 | * This is not really for external use - but the ENC-03 gyro modules needs it. |
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193 | */ |
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2015 | - | 194 | //extern volatile int16_t rawGyroSum[3]; |
1612 | dongfang | 195 | |
196 | /* |
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1645 | - | 197 | * The acceleration values that this module outputs. They are zero based. |
1612 | dongfang | 198 | */ |
2015 | - | 199 | extern int16_t acc[3]; |
200 | extern int16_t filteredAcc[3]; |
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1872 | - | 201 | // extern volatile int32_t stronglyFilteredAcc[3]; |
1612 | dongfang | 202 | |
203 | /* |
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1775 | - | 204 | * Diagnostics: Gyro noise level because of motor vibrations. The variables |
205 | * only really reflect the noise level when the copter stands still but with |
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206 | * its motors running. |
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207 | */ |
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2015 | - | 208 | extern uint16_t gyroNoisePeak[3]; |
209 | extern uint16_t accNoisePeak[3]; |
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1775 | - | 210 | |
211 | /* |
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212 | * Air pressure. |
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1961 | - | 213 | * The sensor has a sensitivity of 45 mV/kPa. |
1970 | - | 214 | * An approximate p(h) formula is = p(h[m])[kPa] = p_0 - 11.95 * 10^-3 * h |
215 | * p(h[m])[kPa] = 101.3 - 11.95 * 10^-3 * h |
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216 | * 11.95 * 10^-3 * h = 101.3 - p[kPa] |
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217 | * h = (101.3 - p[kPa])/0.01195 |
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218 | * That is: dV = -45 mV * 11.95 * 10^-3 dh = -0.53775 mV / m. |
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219 | * That is, with 38.02 * 1.024 / 3 steps per mV: -7 steps / m |
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220 | |||
221 | Display pressures |
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222 | 4165 mV-->1084.7 |
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223 | 4090 mV-->1602.4 517.7 |
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224 | 3877 mV-->3107.8 1503.4 |
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225 | |||
226 | 4165 mV-->1419.1 |
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227 | 3503 mV-->208.1 |
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228 | Diff.: 1211.0 |
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229 | |||
230 | Calculated Vout = 5V(.009P-0.095) --> 5V .009P = Vout + 5V 0.095 --> P = (Vout + 5V 0.095)/(5V 0.009) |
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231 | 4165 mV = 5V(0.009P-0.095) P = 103.11 kPa h = -151.4m |
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232 | 4090 mV = 5V(0.009P-0.095) P = 101.44 kPa h = -11.7m 139.7m |
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233 | 3877 mV = 5V(0.009P-0.095) P = 96.7 kPa h = 385m 396.7m |
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234 | |||
235 | 4165 mV = 5V(0.009P-0.095) P = 103.11 kPa h = -151.4m |
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236 | 3503 mV = 5V(0.009P-0.095) P = 88.4 kPa h = 384m Diff: 1079.5m |
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237 | Pressure at sea level: 101.3 kPa. voltage: 5V * (0.009P-0.095) = 4.0835V |
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238 | This is OCR2 = 143.15 at 1.5V in --> simple pressure = |
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239 | */ |
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240 | |||
241 | #define AIRPRESSURE_SUMMATION_FACTOR 14 |
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1775 | - | 242 | #define AIRPRESSURE_FILTER 8 |
243 | // Minimum A/D value before a range change is performed. |
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244 | #define MIN_RAWPRESSURE (200 * 2) |
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245 | // Maximum A/D value before a range change is performed. |
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246 | #define MAX_RAWPRESSURE (1023 * 2 - MIN_RAWPRESSURE) |
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247 | |||
1796 | - | 248 | #define MIN_RANGES_EXTRAPOLATION 15 |
249 | #define MAX_RANGES_EXTRAPOLATION 240 |
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1775 | - | 250 | |
251 | #define PRESSURE_EXTRAPOLATION_COEFF 25L |
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252 | #define AUTORANGE_WAIT_FACTOR 1 |
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253 | |||
1970 | - | 254 | #define ABS_ALTITUDE_OFFSET 108205 |
255 | |||
2015 | - | 256 | extern uint16_t simpleAirPressure; |
1775 | - | 257 | /* |
258 | * At saturation, the filteredAirPressure may actually be (simulated) negative. |
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259 | */ |
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2015 | - | 260 | extern int32_t filteredAirPressure; |
1775 | - | 261 | |
262 | /* |
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1612 | dongfang | 263 | * Flag: Interrupt handler has done all A/D conversion and processing. |
264 | */ |
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265 | extern volatile uint8_t analogDataReady; |
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266 | |||
267 | void analog_init(void); |
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268 | |||
1952 | - | 269 | /* |
2015 | - | 270 | * This is really only for use for the ENC-03 code module, which needs to get the raw value |
271 | * for its calibration. The raw value should not be used for anything else. |
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272 | */ |
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273 | uint16_t rawGyroValue(uint8_t axis); |
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274 | |||
275 | /* |
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1952 | - | 276 | * Start the conversion cycle. It will stop automatically. |
277 | */ |
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278 | void startAnalogConversionCycle(void); |
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1612 | dongfang | 279 | |
1952 | - | 280 | /* |
281 | * 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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282 | */ |
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1955 | - | 283 | void analog_update(void); |
1612 | dongfang | 284 | |
285 | /* |
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1961 | - | 286 | * Read gyro and acc.meter calibration from EEPROM. |
1612 | dongfang | 287 | */ |
1961 | - | 288 | void analog_setNeutral(void); |
1612 | dongfang | 289 | |
290 | /* |
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1961 | - | 291 | * Zero-offset gyros and write the calibration data to EEPROM. |
1612 | dongfang | 292 | */ |
1961 | - | 293 | void analog_calibrateGyros(void); |
294 | |||
295 | /* |
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296 | * Zero-offset accelerometers and write the calibration data to EEPROM. |
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297 | */ |
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1612 | dongfang | 298 | void analog_calibrateAcc(void); |
299 | #endif //_ANALOG_H |