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Fix incorrect Vref calibration

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The formula used to compute VREF from VREFINT and VREFINTCAL was incorrect.

Also, as correct formulae for VREF and TEMPSENSOR incorporate lots of
MCU dependent variables and constants, a new driver level service was
added to convert ADC values to VREF voltage or temperature.
This commit is contained in:
jflyper 2019-07-21 02:09:39 +09:00
parent d8b74db2dc
commit 9d7cfb1e79
6 changed files with 71 additions and 37 deletions
Download patch file Download diff file Expand all files Collapse all files

30
src/main/drivers/adc.c
View file

@ -46,13 +46,6 @@ volatile FAST_RAM_ZERO_INIT uint16_t adcValues[ADC_CHANNEL_COUNT];
volatile uint16_t adcValues[ADC_CHANNEL_COUNT];
#endif
#ifdef USE_ADC_INTERNAL
uint16_t adcTSCAL1;
uint16_t adcTSCAL2;
int16_t adcTSSlopeK;
uint16_t adcVREFINTCAL;
#endif
uint8_t adcChannelByTag(ioTag_t ioTag)
{
for (uint8_t i = 0; i < ARRAYLEN(adcTagMap); i++) {
@ -132,6 +125,29 @@ bool adcVerifyPin(ioTag_t tag, ADCDevice device)
return false;
}
#ifdef USE_ADC_INTERNAL
int32_t adcVREFINTCAL; // ADC value (12-bit) of band gap with Vref = VREFINTCAL_VREF
int32_t adcTSCAL1;
int32_t adcTSCAL2;
int32_t adcTSSlopeK;
uint16_t adcInternalCompensateVref(uint16_t vrefAdcValue)
{
// This is essentially a tuned version of
// __HAL_ADC_CALC_VREFANALOG_VOLTAGE(vrefAdcValue, ADC_RESOLUTION_12B);
return (uint16_t)((uint32_t)(adcVREFINTCAL * VREFINT_CAL_VREF) / vrefAdcValue);
}
int16_t adcInternalComputeTemperature(uint16_t tempAdcValue, uint16_t vrefValue)
{
// This is essentially a tuned version of
// __HAL_ADC_CALC_TEMPERATURE(vrefValue, tempAdcValue, ADC_RESOLUTION_12B);
return ((((int32_t)((tempAdcValue * vrefValue) / TEMPSENSOR_CAL_VREFANALOG) - adcTSCAL1) * adcTSSlopeK) + 500) / 1000 + TEMPSENSOR_CAL1_TEMP;
}
#endif // USE_ADC_INTERNAL
#else
uint16_t adcGetChannel(uint8_t channel)
{

7
src/main/drivers/adc.h
View file

@ -91,15 +91,12 @@ void adcInit(const struct adcConfig_s *config);
uint16_t adcGetChannel(uint8_t channel);
#ifdef USE_ADC_INTERNAL
extern uint16_t adcVREFINTCAL;
extern uint16_t adcTSCAL1;
extern uint16_t adcTSCAL2;
extern int16_t adcTSSlopeK;
bool adcInternalIsBusy(void);
void adcInternalStartConversion(void);
uint16_t adcInternalReadVrefint(void);
uint16_t adcInternalReadTempsensor(void);
uint16_t adcInternalCompensateVref(uint16_t vrefAdcValue);
int16_t adcInternalComputeTemperature(uint16_t tempAdcValue, uint16_t vrefValue);
#endif
#if !defined(SIMULATOR_BUILD)

44
src/main/drivers/adc_impl.h
View file

@ -80,6 +80,13 @@ typedef struct adcDevice_s {
#endif
} adcDevice_t;
#ifdef USE_ADC_INTERNAL
extern int32_t adcVREFINTCAL; // ADC value (12-bit) of band gap with Vref = VREFINTCAL_VREF
extern int32_t adcTSCAL1;
extern int32_t adcTSCAL2;
extern int32_t adcTSSlopeK;
#endif
extern const adcDevice_t adcHardware[];
extern const adcTagMap_t adcTagMap[ADC_TAG_MAP_COUNT];
extern adcOperatingConfig_t adcOperatingConfig[ADC_CHANNEL_COUNT];
@ -92,3 +99,40 @@ bool adcVerifyPin(ioTag_t tag, ADCDevice device);
// Marshall values in DMA instance/channel based order to adcChannel based order.
// Required for multi DMA instance implementation
void adcGetChannelValues(void);
//
// VREFINT and TEMPSENSOR related definitions
// These are shared among common adc.c and MCU dependent adc_stm32XXX.c
//
#ifdef STM32F7
// STM32F7 HAL library V1.12.0 defines VREFINT and TEMPSENSOR in stm32f7xx_ll_adc.h,
// which is not included from stm32f7xx_hal_adc.h
// We manually copy required lines here.
// XXX V1.14.0 may solve this problem
#define VREFINT_CAL_VREF ( 3300U) /* Analog voltage reference (Vref+) value with which temperature sensor has been calibrated in production (tolerance: +-10 mV) (unit: mV). */
#define TEMPSENSOR_CAL1_TEMP (( int32_t) 30) /* Internal temperature sensor, temperature at which temperature sensor has been calibrated in production for data into TEMPSENSOR_CAL1_ADDR (tolerance: +-5 DegC) (unit: DegC). */
#define TEMPSENSOR_CAL2_TEMP (( int32_t) 110) /* Internal temperature sensor, temperature at which temperature sensor has been calibrated in production for data into TEMPSENSOR_CAL2_ADDR (tolerance: +-5 DegC) (unit: DegC). */
#define TEMPSENSOR_CAL_VREFANALOG ( 3300U) /* Analog voltage reference (Vref+) voltage with which temperature sensor has been calibrated in production (+-10 mV) (unit: mV). */
// These addresses are incorrectly defined in stm32f7xx_ll_adc.h
#if defined(STM32F745xx) || defined(STM32F746xx) || defined(STM32F765xx)
// F745xx_F746xx and F765xx_F767xx_F769xx
#define VREFINT_CAL_ADDR ((uint16_t*) (0x1FF0F44A))
#define TEMPSENSOR_CAL1_ADDR ((uint16_t*) (0x1FF0F44C))
#define TEMPSENSOR_CAL2_ADDR ((uint16_t*) (0x1FF0F44E))
#elif defined(STM32F722xx)
// F72x_F73x
#define VREFINT_CAL_ADDR ((uint16_t*) (0x1FF07A2A))
#define TEMPSENSOR_CAL1_ADDR ((uint16_t*) (0x1FF07A2C))
#define TEMPSENSOR_CAL2_ADDR ((uint16_t*) (0x1FF07A2E))
#endif
#endif // STM32F7
#ifdef STM32F4
// STM32F4 stdlib does not define any of these
#define VREFINT_CAL_VREF (3300U)
#define TEMPSENSOR_CAL_VREFANALOG (3300U)
#define TEMPSENSOR_CAL1_TEMP ((int32_t) 30)
#define TEMPSENSOR_CAL2_TEMP ((int32_t) 110)
#endif

20
src/main/drivers/adc_stm32f7xx.c
View file

@ -38,26 +38,6 @@
#include "pg/adc.h"
// Copied from stm32f7xx_ll_adc.h
#define VREFINT_CAL_VREF ( 3300U) /* Analog voltage reference (Vref+) value with which temperature sensor has been calibrated in production (tolerance: +-10 mV) (unit: mV). */
#define TEMPSENSOR_CAL1_TEMP (( int32_t) 30) /* Internal temperature sensor, temperature at which temperature sensor has been calibrated in production for data into TEMPSENSOR_CAL1_ADDR (tolerance: +-5 DegC) (unit: DegC). */
#define TEMPSENSOR_CAL2_TEMP (( int32_t) 110) /* Internal temperature sensor, temperature at which temperature sensor has been calibrated in production for data into TEMPSENSOR_CAL2_ADDR (tolerance: +-5 DegC) (unit: DegC). */
#define TEMPSENSOR_CAL_VREFANALOG ( 3300U) /* Analog voltage reference (Vref+) voltage with which temperature sensor has been calibrated in production (+-10 mV) (unit: mV). */
// These addresses are incorrectly defined in stm32f7xx_ll_adc.h
#if defined(STM32F745xx) || defined(STM32F746xx) || defined(STM32F765xx)
// F745xx_F746xx and F765xx_F767xx_F769xx
#define VREFINT_CAL_ADDR ((uint16_t*) (0x1FF0F44A))
#define TEMPSENSOR_CAL1_ADDR ((uint16_t*) (0x1FF0F44C))
#define TEMPSENSOR_CAL2_ADDR ((uint16_t*) (0x1FF0F44E))
#elif defined(STM32F722xx)
// F72x_F73x
#define VREFINT_CAL_ADDR ((uint16_t*) (0x1FF07A2A))
#define TEMPSENSOR_CAL1_ADDR ((uint16_t*) (0x1FF07A2C))
#define TEMPSENSOR_CAL2_ADDR ((uint16_t*) (0x1FF07A2E))
#endif
const adcDevice_t adcHardware[] = {
{
.ADCx = ADC1,

6
src/main/sensors/adcinternal.c
View file

@ -87,10 +87,8 @@ void adcInternalProcess(timeUs_t currentTimeUs)
adcVrefintValue = updateMovingAverageUint16(&adcVrefintAverageState, vrefintSample);
adcTempsensorValue = updateMovingAverageUint16(&adcTempsensorAverageState, tempsensorSample);
vrefMv = 3300 * adcVrefintValue / adcVREFINTCAL;
int32_t adcTempsensorAdjusted = (int32_t)(adcTempsensorValue * 3300) / vrefMv;
coreTemperature = ((adcTempsensorAdjusted - adcTSCAL1) * adcTSSlopeK + 30 * 1000 + 500) / 1000;
vrefMv = adcInternalCompensateVref(adcVrefintValue);
coreTemperature = adcInternalComputeTemperature(adcTempsensorValue, vrefMv);
DEBUG_SET(DEBUG_ADC_INTERNAL, 0, coreTemperature);
DEBUG_SET(DEBUG_ADC_INTERNAL, 1, vrefintSample);

1
src/main/target/OMNINXT/hardware_revision.c
View file

@ -150,7 +150,6 @@ static uint16_t adcIDDetectReadVrefint(void)
#endif
#if defined(OMNINXT7)
#define VREFINT_CAL_ADDR 0x1FF07A2A
#include "drivers/adc_impl.h"