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886 | killagreg | 1 | /* |
2 | |||
3 | Copyright 2008, by Killagreg |
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4 | |||
5 | This program (files mm3.c and mm3.h) is free software; you can redistribute it and/or modify |
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6 | it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; |
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7 | either version 3 of the License, or (at your option) any later version. |
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8 | This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; |
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9 | without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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10 | GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License |
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11 | along with this program. If not, see <http://www.gnu.org/licenses/>. |
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12 | |||
13 | Please note: The original implementation was done by Niklas Nold. |
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14 | All the other files for the project "Mikrokopter" by H. Buss are under the license (license_buss.txt) published by www.mikrokopter.de |
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15 | */ |
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16 | #include <stdlib.h> |
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17 | #include <avr/io.h> |
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18 | #include <avr/interrupt.h> |
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19 | #include <inttypes.h> |
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20 | |||
21 | #include "mm3.h" |
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22 | #include "main.h" |
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23 | #include "mymath.h" |
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24 | #include "fc.h" |
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25 | #include "timer0.h" |
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26 | #include "rc.h" |
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27 | #include "eeprom.h" |
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28 | #include "printf_P.h" |
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29 | |||
30 | #define MAX_AXIS_VALUE 500 |
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31 | |||
32 | |||
33 | typedef struct |
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34 | { |
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35 | uint8_t STATE; |
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36 | uint16_t DRDY; |
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37 | uint8_t AXIS; |
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38 | int16_t x_axis; |
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39 | int16_t y_axis; |
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40 | int16_t z_axis; |
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41 | } MM3_working_t; |
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42 | |||
43 | |||
44 | // MM3 State Machine |
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45 | #define MM3_STATE_RESET 0 |
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46 | #define MM3_STATE_START_TRANSFER 1 |
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47 | #define MM3_STATE_WAIT_DRDY 2 |
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48 | #define MM3_STATE_DRDY 3 |
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49 | #define MM3_STATE_BYTE2 4 |
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50 | |||
51 | #define MM3_X_AXIS 0x01 |
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52 | #define MM3_Y_AXIS 0x02 |
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53 | #define MM3_Z_AXIS 0x03 |
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54 | |||
55 | |||
56 | #define MM3_PERIOD_32 0x00 |
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57 | #define MM3_PERIOD_64 0x10 |
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58 | #define MM3_PERIOD_128 0x20 |
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59 | #define MM3_PERIOD_256 0x30 |
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60 | #define MM3_PERIOD_512 0x40 |
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61 | #define MM3_PERIOD_1024 0x50 |
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62 | #define MM3_PERIOD_2048 0x60 |
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63 | #define MM3_PERIOD_4096 0x70 |
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64 | |||
963 | blackking | 65 | #if defined(USE_WALTER_EXT) // walthers board |
962 | blackking | 66 | // Output Pins (J9)PC6->MM3_SS ,(J8)PB2->MM3_RESET |
67 | #define MM3_SS_PORT PORTC //J9->MM3_SS |
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68 | #define MM3_SS_DDR DDRC |
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69 | #define MM3_SS_PIN PC6 |
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70 | #define MM3_RESET_PORT PORTB //J8->MM3_RESET |
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71 | #define MM3_RESET_DDR DDRB |
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72 | #define MM3_RESET_PIN PB2 |
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963 | blackking | 73 | #elif defined(USE_NICK666) // nick666 version 0.67g |
962 | blackking | 74 | #define MM3_SS_PORT PORTD //J5->MM3_SS |
75 | #define MM3_SS_DDR DDRD |
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76 | #define MM3_SS_PIN PD3 |
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77 | #define MM3_RESET_PORT PORTB //J8->MM3_RESET |
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78 | #define MM3_RESET_DDR DDRB |
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79 | #define MM3_RESET_PIN PB2 |
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80 | #else // killagregs board |
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81 | // Output Pins PC4->MM3_SS ,PC5->MM3_RESET |
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82 | #define MM3_SS_PORT PORTC |
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83 | #define MM3_SS_DDR DDRC |
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84 | #define MM3_SS_PIN PC4 |
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85 | #define MM3_RESET_PORT PORTC |
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86 | #define MM3_RESET_DDR DDRC |
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87 | #define MM3_RESET_PIN PC5 |
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88 | #endif |
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89 | |||
90 | #define MM3_SS_ON MM3_SS_PORT &= ~(1<<MM3_SS_PIN); |
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91 | #define MM3_SS_OFF MM3_SS_PORT |= (1<<MM3_SS_PIN); |
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92 | #define MM3_RESET_ON MM3_RESET_PORT |= (1<<MM3_RESET_PIN); |
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93 | #define MM3_RESET_OFF MM3_RESET_PORT &= ~(1<<MM3_RESET_PIN); |
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94 | |||
95 | |||
96 | |||
886 | killagreg | 97 | MM3_calib_t MM3_calib; |
98 | volatile MM3_working_t MM3; |
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99 | volatile uint8_t MM3_Timeout = 0; |
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100 | |||
101 | |||
102 | |||
103 | /*********************************************/ |
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104 | /* Initialize Interface to MM3 Compass */ |
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105 | /*********************************************/ |
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106 | void MM3_Init(void) |
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107 | { |
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108 | uint8_t sreg = SREG; |
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109 | |||
110 | cli(); |
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111 | |||
112 | // Configure Pins for SPI |
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113 | // set SCK (PB7), MOSI (PB5) as output |
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114 | DDRB |= (1<<DDB7)|(1<<DDB5); |
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115 | // set MISO (PB6) as input |
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116 | DDRB &= ~(1<<DDB6); |
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117 | |||
962 | blackking | 118 | |
119 | // Output Pins MM3_SS ,MM3_RESET |
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120 | MM3_SS_DDR |= (1<<MM3_SS_PIN); |
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121 | MM3_RESET_DDR |= (1<<MM3_RESET_PIN); |
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886 | killagreg | 122 | // set pins permanent to low |
962 | blackking | 123 | MM3_SS_PORT &= ~((1<<MM3_SS_PIN)); |
124 | MM3_RESET_PORT &= ~((1<<MM3_RESET_PIN)); |
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886 | killagreg | 125 | |
126 | // Initialize SPI-Interface |
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127 | // Enable interrupt (SPIE=1) |
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128 | // Enable SPI bus (SPE=1) |
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129 | // MSB transmitted first (DORD = 0) |
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130 | // Master SPI Mode (MSTR=1) |
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131 | // Clock polarity low when idle (CPOL=0) |
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132 | // Clock phase sample at leading edge (CPHA=0) |
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133 | // Clock rate = SYSCLK/128 (SPI2X=0, SPR1=1, SPR0=1) 20MHz/128 = 156.25kHz |
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134 | SPCR = (1<<SPIE)|(1<<SPE)|(0<<DORD)|(1<<MSTR)|(0<<CPOL)|(0<<CPHA)|(1<<SPR1)|(1<<SPR0); |
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135 | SPSR &= ~(1<<SPI2X); |
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136 | |||
137 | // Init Statemachine |
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138 | MM3.AXIS = MM3_X_AXIS; |
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139 | MM3.STATE = MM3_STATE_RESET; |
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140 | |||
141 | // Read calibration from EEprom |
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142 | MM3_calib.X_off = (int8_t)GetParamByte(PID_MM3_X_OFF); |
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143 | MM3_calib.Y_off = (int8_t)GetParamByte(PID_MM3_Y_OFF); |
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144 | MM3_calib.Z_off = (int8_t)GetParamByte(PID_MM3_Z_OFF); |
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145 | MM3_calib.X_range = (int16_t)GetParamWord(PID_MM3_X_RANGE); |
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146 | MM3_calib.Y_range = (int16_t)GetParamWord(PID_MM3_Y_RANGE); |
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147 | MM3_calib.Z_range = (int16_t)GetParamWord(PID_MM3_Z_RANGE); |
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148 | |||
149 | MM3_Timeout = 0; |
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150 | |||
151 | SREG = sreg; |
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152 | } |
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153 | |||
154 | |||
155 | /*********************************************/ |
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156 | /* Get Data from MM3 */ |
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157 | /*********************************************/ |
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158 | void MM3_Update(void) // called every 102.4 µs by timer 0 ISR |
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159 | { |
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160 | switch (MM3.STATE) |
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161 | { |
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162 | case MM3_STATE_RESET: |
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962 | blackking | 163 | MM3_SS_ON // select slave |
164 | MM3_RESET_ON // RESET to High, MM3 Reset |
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886 | killagreg | 165 | MM3.STATE = MM3_STATE_START_TRANSFER; |
166 | return; |
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167 | |||
168 | case MM3_STATE_START_TRANSFER: |
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962 | blackking | 169 | MM3_RESET_OFF // RESET auf Low (was 102.4 µs at high level) |
886 | killagreg | 170 | // write to SPDR triggers automatically the transfer MOSI MISO |
171 | // MM3 Period, + AXIS code |
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172 | switch(MM3.AXIS) |
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173 | { |
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174 | case MM3_X_AXIS: |
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175 | SPDR = MM3_PERIOD_256 + MM3_X_AXIS; |
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176 | break; |
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177 | case MM3_Y_AXIS: |
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178 | SPDR = MM3_PERIOD_256 + MM3_Y_AXIS; |
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179 | break; |
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180 | case MM3_Z_AXIS: |
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181 | SPDR = MM3_PERIOD_256 + MM3_Z_AXIS; |
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182 | break; |
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183 | default: |
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184 | MM3.AXIS = MM3_X_AXIS; |
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185 | MM3.STATE = MM3_STATE_RESET; |
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186 | return; |
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187 | } |
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188 | |||
189 | // DRDY line is not connected, therefore |
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190 | // wait before reading data back |
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191 | MM3.DRDY = SetDelay(8); // wait 8ms for data ready |
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192 | MM3.STATE = MM3_STATE_WAIT_DRDY; |
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193 | return; |
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194 | |||
195 | case MM3_STATE_WAIT_DRDY: |
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196 | if (CheckDelay(MM3.DRDY)) |
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197 | { |
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198 | // write something into SPDR to trigger data reading |
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199 | SPDR = 0x00; |
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200 | MM3.STATE = MM3_STATE_DRDY; |
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201 | } |
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202 | return; |
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203 | } |
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204 | } |
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205 | |||
206 | |||
207 | /*********************************************/ |
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208 | /* Interrupt SPI transfer complete */ |
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209 | /*********************************************/ |
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210 | ISR(SPI_STC_vect) |
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211 | { |
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212 | static int8_t tmp; |
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213 | int16_t value; |
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214 | |||
215 | switch (MM3.STATE) |
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216 | { |
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217 | // 1st byte received |
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218 | case MM3_STATE_DRDY: |
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219 | tmp = SPDR; // store 1st byte |
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220 | SPDR = 0x00; // trigger transfer of 2nd byte |
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221 | MM3.STATE = MM3_STATE_BYTE2; |
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222 | return; |
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223 | |||
224 | case MM3_STATE_BYTE2: // 2nd byte received |
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225 | value = (int16_t)tmp; // combine the 1st and 2nd byte to a word |
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226 | value <<= 8; // shift 1st byte to MSB-Position |
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227 | value |= (int16_t)SPDR; // add 2nd byte |
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228 | |||
229 | if(abs(value) < MAX_AXIS_VALUE) // ignore spikes |
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230 | { |
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231 | switch (MM3.AXIS) |
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232 | { |
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233 | case MM3_X_AXIS: |
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234 | MM3.x_axis = value; |
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235 | MM3.AXIS = MM3_Y_AXIS; |
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236 | break; |
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237 | case MM3_Y_AXIS: |
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238 | MM3.y_axis = value; |
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239 | MM3.AXIS = MM3_Z_AXIS; |
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240 | break; |
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241 | case MM3_Z_AXIS: |
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242 | MM3.z_axis = value; |
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243 | MM3.AXIS = MM3_X_AXIS; |
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244 | break; |
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245 | default: |
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246 | MM3.AXIS = MM3_X_AXIS; |
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247 | break; |
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248 | } |
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249 | } |
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962 | blackking | 250 | MM3_SS_OFF // deselect slave |
886 | killagreg | 251 | MM3.STATE = MM3_STATE_RESET; |
252 | // Update timeout is called every 102.4 µs. |
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253 | // It takes 2 cycles to write a measurement data request for one axis and |
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254 | // at at least 8 ms / 102.4 µs = 79 cycles to read the requested data back. |
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255 | // I.e. 81 cycles * 102.4 µs = 8.3ms per axis. |
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256 | // The two function accessing the MM3 Data - MM3_Calibrate() and MM3_Heading() - |
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257 | // decremtent the MM3_Timeout every 100 ms. |
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258 | // incrementing the counter by 1 every 8.3 ms is sufficient to avoid a timeout. |
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259 | if ((MM3.x_axis != MM3.y_axis) || (MM3.x_axis != MM3.z_axis) || (MM3.y_axis != MM3.z_axis)) |
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260 | { // if all axis measurements give diffrent readings the data should be valid |
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261 | if(MM3_Timeout < 20) MM3_Timeout++; |
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262 | } |
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263 | else // something is very strange here |
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264 | { |
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265 | if(MM3_Timeout ) MM3_Timeout--; |
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266 | } |
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267 | return; |
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268 | |||
269 | default: |
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270 | return; |
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271 | } |
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272 | } |
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273 | |||
274 | |||
275 | /*********************************************/ |
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276 | /* Calibrate Compass */ |
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277 | /*********************************************/ |
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278 | void MM3_Calibrate(void) |
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279 | { |
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280 | static int16_t x_min, x_max, y_min, y_max, z_min, z_max; |
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281 | |||
282 | switch(CompassCalState) |
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283 | { |
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284 | case 1: // change to x-y axis |
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285 | x_min = 10000; |
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286 | x_max = -10000; |
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287 | y_min = 10000; |
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288 | y_max = -10000; |
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289 | z_min = 10000; |
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290 | z_max = -10000; |
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291 | break; |
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292 | case 2: |
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293 | // find Min and Max of the X- and Y-Axis |
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294 | if(MM3.x_axis < x_min) x_min = MM3.x_axis; |
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295 | if(MM3.x_axis > x_max) x_max = MM3.x_axis; |
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296 | if(MM3.y_axis < y_min) y_min = MM3.y_axis; |
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297 | if(MM3.y_axis > y_max) y_max = MM3.y_axis; |
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298 | break; |
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299 | case 3: |
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300 | // change to z-Axis |
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301 | break; |
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302 | case 4: |
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936 | killagreg | 303 | RED_ON; // find Min and Max of the Z-axis |
886 | killagreg | 304 | if(MM3.z_axis < z_min) z_min = MM3.z_axis; |
305 | if(MM3.z_axis > z_max) z_max = MM3.z_axis; |
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306 | break; |
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307 | case 5: |
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308 | // calc range of all axis |
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309 | MM3_calib.X_range = (x_max - x_min); |
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310 | MM3_calib.Y_range = (y_max - y_min); |
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311 | MM3_calib.Z_range = (z_max - z_min); |
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312 | |||
313 | // calc offset of all axis |
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314 | MM3_calib.X_off = (x_max + x_min) / 2; |
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315 | MM3_calib.Y_off = (y_max + y_min) / 2; |
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316 | MM3_calib.Z_off = (z_max + z_min) / 2; |
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317 | |||
318 | // save to EEProm |
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319 | SetParamByte(PID_MM3_X_OFF, (uint8_t)MM3_calib.X_off); |
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320 | SetParamByte(PID_MM3_Y_OFF, (uint8_t)MM3_calib.Y_off); |
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321 | SetParamByte(PID_MM3_Z_OFF, (uint8_t)MM3_calib.Z_off); |
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322 | SetParamWord(PID_MM3_X_RANGE, (uint16_t)MM3_calib.X_range); |
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323 | SetParamWord(PID_MM3_Y_RANGE, (uint16_t)MM3_calib.Y_range); |
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324 | SetParamWord(PID_MM3_Z_RANGE, (uint16_t)MM3_calib.Z_range); |
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325 | |||
326 | CompassCalState = 0; |
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327 | break; |
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328 | default: |
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329 | CompassCalState = 0; |
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330 | break; |
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331 | } |
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332 | } |
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333 | |||
334 | |||
335 | /* |
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336 | void MM3_Calibrate(void) |
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337 | { |
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338 | static uint8_t debugcounter = 0; |
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339 | int16_t x_min = 0, x_max = 0, y_min = 0, y_max = 0, z_min = 0, z_max = 0; |
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340 | uint8_t measurement = 50, beeper = 0; |
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341 | uint16_t timer; |
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342 | |||
343 | GRN_ON; |
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936 | killagreg | 344 | RED_OFF; |
886 | killagreg | 345 | |
346 | // get maximum and minimum reading of all axis |
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347 | while (measurement) |
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348 | { |
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349 | // reset range markers if yawstick ist leftmost |
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350 | if(PPM_in[ParamSet.ChannelAssignment[CH_YAW]] > 100) |
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351 | { |
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352 | x_min = 0; |
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353 | x_max = 0; |
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354 | y_min = 0; |
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355 | y_max = 0; |
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356 | z_min = 0; |
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357 | z_max = 0; |
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358 | } |
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359 | |||
360 | if (MM3.x_axis > x_max) x_max = MM3.x_axis; |
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361 | else if (MM3.x_axis < x_min) x_min = MM3.x_axis; |
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362 | |||
363 | if (MM3.y_axis > y_max) y_max = MM3.y_axis; |
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364 | else if (MM3.y_axis < y_min) y_min = MM3.y_axis; |
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365 | |||
366 | if (MM3.z_axis > z_max) z_max = MM3.z_axis; |
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367 | else if (MM3.z_axis < z_min) z_min = MM3.z_axis; |
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368 | |||
369 | if (!beeper) |
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370 | { |
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936 | killagreg | 371 | RED_FLASH; |
886 | killagreg | 372 | GRN_FLASH; |
373 | BeepTime = 50; |
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374 | beeper = 50; |
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375 | } |
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376 | beeper--; |
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377 | // loop with period of 10 ms / 100 Hz |
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378 | timer = SetDelay(10); |
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379 | while(!CheckDelay(timer)); |
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380 | |||
381 | if(debugcounter++ > 30) |
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382 | { |
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383 | printf("\n\rXMin:%4d, XMax:%4d, YMin:%4d, YMax:%4d, ZMin:%4d, ZMax:%4d",x_min,x_max,y_min,y_max,z_min,z_max); |
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384 | debugcounter = 0; |
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385 | } |
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386 | |||
911 | killagreg | 387 | // If gas is less than 100, stop calibration with a delay of 0.5 seconds |
388 | if (PPM_in[ParamSet.ChannelAssignment[CH_GAS]] < 100) measurement--; |
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886 | killagreg | 389 | } |
390 | // Rage of all axis |
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391 | MM3_calib.X_range = (x_max - x_min); |
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392 | MM3_calib.Y_range = (y_max - y_min); |
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393 | MM3_calib.Z_range = (z_max - z_min); |
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394 | |||
395 | // Offset of all axis |
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396 | MM3_calib.X_off = (x_max + x_min) / 2; |
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397 | MM3_calib.Y_off = (y_max + y_min) / 2; |
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398 | MM3_calib.Z_off = (z_max + z_min) / 2; |
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399 | |||
400 | // save to EEProm |
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401 | SetParamByte(PID_MM3_X_OFF, (uint8_t)MM3_calib.X_off); |
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402 | SetParamByte(PID_MM3_Y_OFF, (uint8_t)MM3_calib.Y_off); |
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403 | SetParamByte(PID_MM3_Z_OFF, (uint8_t)MM3_calib.Z_off); |
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404 | SetParamWord(PID_MM3_X_RANGE, (uint16_t)MM3_calib.X_range); |
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405 | SetParamWord(PID_MM3_Y_RANGE, (uint16_t)MM3_calib.Y_range); |
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406 | SetParamWord(PID_MM3_Z_RANGE, (uint16_t)MM3_calib.Z_range); |
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407 | |||
408 | } |
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409 | */ |
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410 | |||
411 | /*********************************************/ |
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412 | /* Calculate north direction (heading) */ |
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413 | /*********************************************/ |
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414 | void MM3_Heading(void) |
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415 | { |
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911 | killagreg | 416 | int32_t sin_nick, cos_nick, sin_roll, cos_roll, sin_yaw, cos_yaw; |
886 | killagreg | 417 | int32_t Hx, Hy, Hz, Hx_corr, Hy_corr; |
418 | int16_t angle; |
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419 | uint16_t div_factor; |
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420 | int16_t heading; |
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421 | |||
422 | if (MM3_Timeout) |
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423 | { |
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424 | // Offset correction and normalization (values of H are +/- 512) |
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425 | Hx = (((int32_t)(MM3.x_axis - MM3_calib.X_off)) * 1024) / (int32_t)MM3_calib.X_range; |
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426 | Hy = (((int32_t)(MM3.y_axis - MM3_calib.Y_off)) * 1024) / (int32_t)MM3_calib.Y_range; |
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427 | Hz = (((int32_t)(MM3.z_axis - MM3_calib.Z_off)) * 1024) / (int32_t)MM3_calib.Z_range; |
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428 | |||
429 | // Compensate the angle of the MM3-arrow to the head of the MK by a yaw rotation transformation |
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430 | // assuming the MM3 board is mounted parallel to the frame. |
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431 | // User Param 4 is used to define the positive angle from the MM3-arrow to the MK heading |
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432 | // in a top view counter clockwise direction. |
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433 | // North is in opposite direction of the small arrow on the MM3 board. |
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434 | // Therefore 180 deg must be added to that angle. |
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435 | angle = ((int16_t)ParamSet.UserParam4 + 180); |
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436 | // wrap angle to interval of 0°- 359° |
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437 | angle += 360; |
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438 | angle %= 360; |
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439 | sin_yaw = (int32_t)(c_sin_8192(angle)); |
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440 | cos_yaw = (int32_t)(c_cos_8192(angle)); |
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441 | |||
442 | Hx_corr = Hx; |
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443 | Hy_corr = Hy; |
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444 | |||
445 | // rotate |
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446 | Hx = (Hx_corr * cos_yaw - Hy_corr * sin_yaw) / 8192; |
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447 | Hy = (Hx_corr * sin_yaw + Hy_corr * cos_yaw) / 8192; |
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448 | |||
449 | |||
450 | // tilt compensation |
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451 | |||
452 | // calibration factor for transforming Gyro Integrals to angular degrees |
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453 | div_factor = (uint16_t)ParamSet.UserParam3 * 8; |
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454 | |||
911 | killagreg | 455 | // calculate sinus cosinus of nick and tilt angle |
456 | angle = (IntegralNick/div_factor); |
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457 | sin_nick = (int32_t)(c_sin_8192(angle)); |
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458 | cos_nick = (int32_t)(c_cos_8192(angle)); |
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886 | killagreg | 459 | |
460 | angle = (IntegralRoll/div_factor); |
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461 | sin_roll = (int32_t)(c_sin_8192(angle)); |
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462 | cos_roll = (int32_t)(c_cos_8192(angle)); |
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463 | |||
911 | killagreg | 464 | Hx_corr = Hx * cos_nick; |
465 | Hx_corr -= Hz * sin_nick; |
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886 | killagreg | 466 | Hx_corr /= 8192; |
467 | |||
468 | Hy_corr = Hy * cos_roll; |
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469 | Hy_corr += Hz * sin_roll; |
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470 | Hy_corr /= 8192; |
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471 | |||
472 | // calculate Heading |
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473 | heading = c_atan2(Hy_corr, Hx_corr); |
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474 | |||
475 | // atan returns angular range from -180 deg to 180 deg in counter clockwise notation |
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476 | // but the compass course is defined in a range from 0 deg to 360 deg clockwise notation. |
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477 | if (heading < 0) heading = -heading; |
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478 | else heading = 360 - heading; |
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479 | } |
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480 | else // MM3_Timeout = 0 i.e now new data from external board |
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481 | { |
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482 | if(!BeepTime) BeepTime = 100; // make noise to signal the compass problem |
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483 | heading = -1; |
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484 | } |
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485 | // update compass values in fc variables |
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486 | CompassHeading = heading; |
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487 | if (CompassHeading < 0) CompassOffCourse = 0; |
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488 | else CompassOffCourse = ((540 + CompassHeading - CompassCourse) % 360) - 180; |
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489 | } |