src/main/sensors/adcinternal.c

   1 /*
   2  * This file is part of Cleanflight and Betaflight.
   3  *
   4  * Cleanflight and Betaflight are free software. You can redistribute
   5  * this software and/or modify this software under the terms of the
   6  * GNU General Public License as published by the Free Software
   7  * Foundation, either version 3 of the License, or (at your option)
   8  * any later version.
   9  *
  10  * Cleanflight and Betaflight are distributed in the hope that they
  11  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  12  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  13  * See the GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this software.
  17  *
  18  * If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <stdbool.h>
  22 #include <stdint.h>
  23
  24 #include "platform.h"
  25
  26 #if defined(USE_ADC_INTERNAL)
  27
  28 #include "build/debug.h"
  29
  30 #include "common/utils.h"
  31
  32 #include "drivers/adc.h"
  33
  34 typedef struct movingAverageStateUint16_s {
  35     uint32_t sum;
  36     uint16_t *values;
  37     uint8_t size;
  38     uint8_t pos;
  39 } movingAverageStateUint16_t;
  40
  41 uint16_t updateMovingAverageUint16(movingAverageStateUint16_t *state, uint16_t newValue)
  42 {
  43     state->sum -= state->values[state->pos];
  44     state->values[state->pos] = newValue;
  45     state->sum += newValue;
  46     state->pos = (state->pos + 1) % state->size;
  47
  48     return state->sum / state->size;
  49 }
  50
  51 static uint16_t adcVrefintValue;
  52 static uint16_t adcVrefintValues[8];
  53 movingAverageStateUint16_t adcVrefintAverageState = { 0, adcVrefintValues, 8, 0 } ;
  54
  55 static uint16_t adcTempsensorValue;
  56 static uint16_t adcTempsensorValues[8];
  57 movingAverageStateUint16_t adcTempsensorAverageState = { 0, adcTempsensorValues, 8, 0 } ;
  58
  59 static int16_t coreTemperature;
  60 static uint16_t vrefMv;
  61
  62 uint16_t getVrefMv(void)
  63 {
  64 #ifdef ADC_VOLTAGE_REFERENCE_MV
  65     return ADC_VOLTAGE_REFERENCE_MV;
  66 #else
  67     return vrefMv;
  68 #endif
  69 }
  70
  71 int16_t getCoreTemperatureCelsius(void)
  72 {
  73     return coreTemperature;
  74 }
  75
  76 void adcInternalProcess(timeUs_t currentTimeUs)
  77 {
  78     UNUSED(currentTimeUs);
  79
  80     if (adcInternalIsBusy()) {
  81         return;
  82     }
  83
  84     uint16_t vrefintSample = adcInternalReadVrefint();
  85     uint16_t tempsensorSample = adcInternalReadTempsensor();
  86
  87     adcVrefintValue = updateMovingAverageUint16(&adcVrefintAverageState, vrefintSample);
  88     adcTempsensorValue = updateMovingAverageUint16(&adcTempsensorAverageState, tempsensorSample);
  89
  90     vrefMv = 3300 * adcVrefintValue / adcVREFINTCAL;
  91
  92     int32_t adcTempsensorAdjusted = (int32_t)(adcTempsensorValue * 3300) / vrefMv;
  93     coreTemperature = ((adcTempsensorAdjusted - adcTSCAL1) * adcTSSlopeK + 30 * 1000 + 500) / 1000;
  94
  95     DEBUG_SET(DEBUG_ADC_INTERNAL, 0, coreTemperature);
  96     DEBUG_SET(DEBUG_ADC_INTERNAL, 1, vrefintSample);
  97     DEBUG_SET(DEBUG_ADC_INTERNAL, 2, tempsensorSample);
  98     DEBUG_SET(DEBUG_ADC_INTERNAL, 3, vrefMv);
  99
 100     adcInternalStartConversion(); // Start next conversion
 101 }
 102
 103 void adcInternalInit(void)
 104 {
 105     // Call adcInternalProcess repeatedly to fill moving average array
 106     for (int i = 0 ; i < 9 ; i++) {
 107         while (adcInternalIsBusy()) {
 108             // empty
 109         }
 110         adcInternalProcess(0);
 111     }
 112 }
 113 #else
 114 uint16_t getVrefMv(void)
 115 {
 116 #ifdef ADC_VOLTAGE_REFERENCE_MV
 117     return ADC_VOLTAGE_REFERENCE_MV;
 118 #else
 119     return 3300;
 120 #endif
 121 }
 122 #endif