Files
stm32samples/F3:F303/MLX90640-allsky/adc.c
2026-05-06 23:30:36 +03:00

281 lines
8.2 KiB
C

/*
* This file is part of the ir-allsky project.
* Copyright 2025 Edward V. Emelianov <edward.emelianoff@gmail.com>.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <math.h>
#ifdef EBUG
#include "strfunc.h"
#endif
#include "adc.h"
/**
* @brief ADCx_array - arrays for ADC channels with median filtering:
* ADC1:
* 0 - Ch0 - ADC1_IN1 - NTC1
* 1 - Ch1 - ADC1_IN2 - NTC2
* 2 - Ch2 - ADC1_IN3 - NTC3
* 3 - Ch3 - ADC1_IN4 - NTC4
* 4 - internal Tsens - ADC1_IN16
* 5 - Vref - ADC1_IN18
* ADC2:
* AIN5/DAC_OUT1 - PA4 - DAC1_OUT1 (onboard heater)
* 6 - PA5 - ADC2_IN2 (DAC output control)
*/
static uint16_t ADC_array[NUMBER_OF_ADC_CHANNELS*9];
TRUE_INLINE void calADC(ADC_TypeDef *chnl){
// calibration
// enable voltage regulator
chnl->CR = 0;
chnl->CR = ADC_CR_ADVREGEN_0;
// wait for 10us
uint16_t ctr = 0;
while(++ctr < 1000){nop();}
// ADCALDIF=0 (single channels)
if((chnl->CR & ADC_CR_ADEN)){
chnl->CR |= ADC_CR_ADSTP;
chnl->CR |= ADC_CR_ADDIS;
}
chnl->CR |= ADC_CR_ADCAL;
while((chnl->CR & ADC_CR_ADCAL) != 0 && ++ctr < 0xfff0){};
chnl->CR = ADC_CR_ADVREGEN_0;
// enable ADC
ctr = 0;
do{
chnl->CR |= ADC_CR_ADEN;
}while((chnl->ISR & ADC_ISR_ADRDY) == 0 && ++ctr < 0xfff0);
}
TRUE_INLINE void enADC(ADC_TypeDef *chnl){
// ADEN->1, wait ADRDY
chnl->CR |= ADC_CR_ADEN;
uint16_t ctr = 0;
while(!(chnl->ISR & ADC_ISR_ADRDY) && ++ctr < 0xffff){}
chnl->CR |= ADC_CR_ADSTART; /* start the ADC conversions */
}
/**
* ADC1 - DMA1_ch1
* ADC2 - DMA2_ch1
*/
// Setup ADC and DAC; ADC/DAC pins should be prepared in gpio_setup
void adc_setup(){
RCC->AHBENR |= RCC_AHBENR_ADC12EN; // Enable clocking
ADC12_COMMON->CCR = ADC_CCR_TSEN | ADC_CCR_VREFEN | ADC_CCR_CKMODE; // enable Tsens and Vref, HCLK/4
calADC(ADC1);
calADC(ADC2);
// ADC1: channels 1,2,3,4,16,18
ADC1->SMPR1 = ADC_SMPR1_SMP0 | ADC_SMPR1_SMP1 | ADC_SMPR1_SMP2 | ADC_SMPR1_SMP3;
ADC1->SMPR2 = ADC_SMPR2_SMP15 | ADC_SMPR2_SMP17;
// 6 conversions in group: 1->2->3->4->16->18
ADC1->SQR1 = (1<<6) | (2<<12) | (3<<18) | (4<<24) | (NUMBER_OF_ADC1_CHANNELS-1);
ADC1->SQR2 = (16<<0) | (18<<6);
// ADC2: channel 2
ADC2->SMPR1 = ADC_SMPR1_SMP1;
ADC2->SQR1 = (2<<6) | (NUMBER_OF_ADC2_CHANNELS-1);
// configure DMA for ADC
RCC->AHBENR |= RCC_AHBENR_DMA1EN | RCC_AHBENR_DMA2EN;
ADC1->CFGR = ADC_CFGR_CONT | ADC_CFGR_DMAEN | ADC_CFGR_DMACFG;
ADC2->CFGR = ADC_CFGR_CONT | ADC_CFGR_DMAEN | ADC_CFGR_DMACFG;
DMA1_Channel1->CPAR = (uint32_t) (&(ADC1->DR));
DMA1_Channel1->CMAR = (uint32_t)(ADC_array);
DMA1_Channel1->CNDTR = NUMBER_OF_ADC1_CHANNELS * 9;
DMA1_Channel1->CCR |= DMA_CCR_MINC | DMA_CCR_MSIZE_0 | DMA_CCR_PSIZE_0 | DMA_CCR_CIRC;
DMA1_Channel1->CCR |= DMA_CCR_EN;
DMA2_Channel1->CPAR = (uint32_t) (&(ADC2->DR));
DMA2_Channel1->CMAR = (uint32_t)(&ADC_array[ADC2START]);
DMA2_Channel1->CNDTR = NUMBER_OF_ADC2_CHANNELS * 9;
DMA2_Channel1->CCR |= DMA_CCR_MINC | DMA_CCR_MSIZE_0 | DMA_CCR_PSIZE_0 | DMA_CCR_CIRC;
DMA2_Channel1->CCR |= DMA_CCR_EN;
enADC(ADC1);
enADC(ADC2);
// enable DAC
RCC->APB1ENR |= RCC_APB1ENR_DAC1EN;
// DAC simple throw out constant value: output buffer disable, DAC ch1 enable
DAC->CR = DAC_CR_BOFF1 | DAC_CR_EN1;
// starting value: 0
DAC1->DHR12R1 = 0;
}
/**
* @brief getADCval - calculate median value for `nch` channel
* @param nch - number of channel
* @return
*/
uint16_t getADCval(uint8_t nch){
if(nch >= NUMBER_OF_ADC_CHANNELS) return 0;
register uint16_t temp;
#define PIX_SORT(a,b) { if ((a)>(b)) PIX_SWAP((a),(b)); }
#define PIX_SWAP(a,b) { temp=(a);(a)=(b);(b)=temp; }
uint16_t p[9];
int adval = (nch >= NUMBER_OF_ADC1_CHANNELS) ? NUMBER_OF_ADC2_CHANNELS : NUMBER_OF_ADC1_CHANNELS;
int addr = (nch >= NUMBER_OF_ADC1_CHANNELS) ? nch - NUMBER_OF_ADC2_CHANNELS + ADC2START: nch;
for(int i = 0; i < 9; ++i, addr += adval) // first we should prepare array for optmed
p[i] = ADC_array[addr];
PIX_SORT(p[1], p[2]) ; PIX_SORT(p[4], p[5]) ; PIX_SORT(p[7], p[8]) ;
PIX_SORT(p[0], p[1]) ; PIX_SORT(p[3], p[4]) ; PIX_SORT(p[6], p[7]) ;
PIX_SORT(p[1], p[2]) ; PIX_SORT(p[4], p[5]) ; PIX_SORT(p[7], p[8]) ;
PIX_SORT(p[0], p[3]) ; PIX_SORT(p[5], p[8]) ; PIX_SORT(p[4], p[7]) ;
PIX_SORT(p[3], p[6]) ; PIX_SORT(p[1], p[4]) ; PIX_SORT(p[2], p[5]) ;
PIX_SORT(p[4], p[7]) ; PIX_SORT(p[4], p[2]) ; PIX_SORT(p[6], p[4]) ;
PIX_SORT(p[4], p[2]) ;
return p[4];
#undef PIX_SORT
#undef PIX_SWAP
}
// get voltage @input nch (V)
float getADCvoltage(uint8_t nch){
float v = getADCval(nch);
v *= getVdd();
v /= 4096.f; // 12bit ADC
return v;
}
// return MCU temperature (degrees of celsius)
float getMCUtemp(){
// make correction on Vdd value
int32_t ADval = getADCval(ADC_TS);
float temperature = (float) *TEMP30_CAL_ADDR - ADval;
temperature *= (110.f - 30.f);
temperature /= (float)(*TEMP30_CAL_ADDR - *TEMP110_CAL_ADDR);
temperature += 30.f;
return(temperature);
}
// return Vdd (V)
float getVdd(){
float vdd = ((float) *VREFINT_CAL_ADDR) * 3.3f; // 3.3V
vdd /= getADCval(ADC_VREF);
return vdd;
}
// R lookup table for T=-10..59 degreesC
#if 0
T=[-10:59]+273.15;
R=1000*exp(3950*(1./T-1/298.15));
for i=1:length(T); printf("\t%.1f,\t// %d \n", R(i), T(i)-273.15); endfor
#endif
static const float Rlut[] = {
5824.6, // -10
5502.8, // -9
5201.1, // -8
4917.9, // -7
4652.2, // -6
4402.6, // -5
4168.1, // -4
3947.7, // -3
3740.5, // -2
3545.5, // -1
3362.1, // 0
3189.3, // 1
3026.6, // 2
2873.3, // 3
2728.8, // 4
2592.5, // 5
2463.9, // 6
2342.5, // 7
2227.9, // 8
2119.7, // 9
2017.5, // 10
1920.8, // 11
1829.4, // 12
1743.0, // 13
1661.2, // 14
1583.7, // 15
1510.4, // 16
1440.9, // 17
1375.1, // 18
1312.7, // 19
1253.5, // 20
1197.4, // 21
1144.1, // 22
1093.6, // 23
1045.6, // 24
1000.0, // 25
956.7, // 26
915.5, // 27
876.4, // 28
839.1, // 29
803.7, // 30
770.0, // 31
737.9, // 32
707.4, // 33
678.3, // 34
650.6, // 35
624.1, // 36
598.9, // 37
574.9, // 38
552.0, // 39
530.1, // 40
509.3, // 41
489.4, // 42
470.3, // 43
452.2, // 44
434.8, // 45
418.2, // 46
402.4, // 47
387.2, // 48
372.7, // 49
358.8, // 50
345.5, // 51
332.8, // 52
320.7, // 53
309.0, // 54
297.8, // 55
287.1, // 56
276.9, // 57
267.1, // 58
257.7, // 59
};
#define LUTSZ (sizeof(Rlut) / sizeof(float))
/**
* @brief getNTCtemp - stupid LUT-search and linear approximation of T by R
* @param nch - channel of ADC for Tx
* @return temperature in degr.C
*/
float getNTCtemp(uint8_t nch){
if(nch > ADC_AIN4) return -300.f; // bad number
uint16_t val = getADCval(nch);
if(val < 5) return -400.f; // short cirquit
else if(val > 4090) return -500.f; // no NTC
float R = 1000.f / (4096.f / val - 1.f); // resistance of NTC
#ifdef EBUG
USB_sendstr("R="); USB_sendstr(float2str(R, 1)); newline();
#endif
int left = 0, right = LUTSZ-1;
if(R > Rlut[0]) right = 1;
else if(R < Rlut[LUTSZ-1]) left = LUTSZ-2;
while(right - left > 1){
int idx = left + (right - left) / 2;
float Rl = Rlut[idx];
if(Rl > R) left = idx + 1;
else right = idx - 1;
}
if(left >= (int)LUTSZ) return 60.f;
float Rleft = Rlut[left], Rright = Rlut[left+1];
float T = (float)left - 9.f - (R - Rright) / (Rleft - Rright);
return T;
}