kopia lustrzana https://github.com/espressif/esp-idf
176 wiersze
6.8 KiB
C
176 wiersze
6.8 KiB
C
/*
|
|
* SPDX-FileCopyrightText: 2019-2024 Espressif Systems (Shanghai) CO LTD
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0
|
|
*/
|
|
|
|
#include <stdint.h>
|
|
#include <stdbool.h>
|
|
#include <string.h>
|
|
#include "esp_types.h"
|
|
#include "esp_err.h"
|
|
#include "esp_log.h"
|
|
#include "esp_check.h"
|
|
#include "esp_efuse_rtc_calib.h"
|
|
#include "hal/adc_ll.h"
|
|
#include "hal/adc_types.h"
|
|
#include "driver/adc_types_legacy.h"
|
|
#include "esp_adc_cal_types_legacy.h"
|
|
#include "../esp_adc_cal_internal_legacy.h"
|
|
|
|
const static char LOG_TAG[] = "ADC_CALI";
|
|
|
|
/* ------------------------ Characterization Constants ---------------------- */
|
|
|
|
// coeff_a is actually a float number
|
|
// it is scaled to put them into uint32_t so that the headers do not have to be changed
|
|
static const int coeff_a_scaling = 65536;
|
|
|
|
/**
|
|
* @note Error Calculation
|
|
* Coefficients for calculating the reading voltage error.
|
|
* Four sets of coefficients for atten0 ~ atten3 respectively.
|
|
*
|
|
* For each item, first element is the Coefficient, second element is the Multiple. (Coefficient / Multiple) is the real coefficient.
|
|
*
|
|
* @note {0,0} stands for unused item
|
|
* @note In case of the overflow, these coefficients are recorded as Absolute Value
|
|
* @note For atten0 ~ 2, error = (K0 * X^0) + (K1 * X^1) + (K2 * X^2); For atten3, error = (K0 * X^0) + (K1 * X^1) + (K2 * X^2) + (K3 * X^3) + (K4 * X^4);
|
|
* @note Above formula is rewritten from the original documentation, please note that the coefficients are re-ordered.
|
|
* @note ADC1 and ADC2 use same coefficients
|
|
*/
|
|
const static uint64_t adc_error_coef_atten[4][5][2] = {
|
|
{{225966470500043, 1e15}, {7265418501948, 1e16}, {109410402681, 1e16}, {0, 0}, {0, 0}}, //atten0
|
|
{{4229623392600516, 1e16}, {731527490903, 1e16}, {88166562521, 1e16}, {0, 0}, {0, 0}}, //atten1
|
|
{{1017859239236435, 1e15}, {97159265299153, 1e16}, {149794028038, 1e16}, {0, 0}, {0, 0}}, //atten2
|
|
{{14912262772850453, 1e16}, {228549975564099, 1e16}, {356391935717, 1e16}, {179964582, 1e16}, {42046, 1e16}} //atten3
|
|
};
|
|
/**
|
|
* Term sign
|
|
* @note ADC1 and ADC2 use same coefficients
|
|
*/
|
|
const static int32_t adc_error_sign[4][5] = {
|
|
{-1, -1, 1, 0, 0}, //atten0
|
|
{ 1, -1, 1, 0, 0}, //atten1
|
|
{-1, -1, 1, 0, 0}, //atten2
|
|
{-1, -1, 1, -1, 1} //atten3
|
|
};
|
|
|
|
/* -------------------- Characterization Helper Data Types ------------------ */
|
|
typedef struct {
|
|
uint32_t voltage;
|
|
uint32_t digi;
|
|
} adc_calib_data_ver1;
|
|
|
|
typedef struct {
|
|
char version_num;
|
|
adc_unit_t adc_num;
|
|
adc_atten_t atten_level;
|
|
union {
|
|
adc_calib_data_ver1 ver1;
|
|
} efuse_data;
|
|
} adc_calib_parsed_info_t;
|
|
|
|
static esp_err_t prepare_calib_data_for(int version_num, adc_unit_t adc_num, adc_atten_t atten, adc_calib_parsed_info_t *parsed_data_storage)
|
|
{
|
|
assert(version_num == 1);
|
|
esp_err_t ret;
|
|
|
|
parsed_data_storage->version_num = version_num;
|
|
parsed_data_storage->adc_num = adc_num;
|
|
parsed_data_storage->atten_level = atten;
|
|
uint32_t voltage, digi;
|
|
/**
|
|
* V1 we don't have calibration data for ADC2, using the efuse data of ADC1.
|
|
* Here passing the `adc_num` is just for compatibility
|
|
*/
|
|
ret = esp_efuse_rtc_calib_get_cal_voltage(version_num, adc_num, atten, &digi, &voltage);
|
|
if (ret != ESP_OK) {
|
|
return ret;
|
|
}
|
|
parsed_data_storage->efuse_data.ver1.voltage = voltage;
|
|
parsed_data_storage->efuse_data.ver1.digi = digi;
|
|
return ret;
|
|
}
|
|
|
|
/* ----------------------- Characterization Functions ----------------------- */
|
|
/*
|
|
* Estimate the (assumed) linear relationship btwn the measured raw value and the voltage
|
|
* with the previously done measurement when the chip was manufactured.
|
|
*/
|
|
static void calculate_characterization_coefficients(const adc_calib_parsed_info_t *parsed_data, esp_adc_cal_characteristics_t *chars)
|
|
{
|
|
ESP_LOGD(LOG_TAG, "Calib V1, Cal Voltage = %"PRId32", Digi out = %"PRId32, parsed_data->efuse_data.ver1.voltage, parsed_data->efuse_data.ver1.digi);
|
|
|
|
chars->coeff_a = coeff_a_scaling * parsed_data->efuse_data.ver1.voltage / parsed_data->efuse_data.ver1.digi;
|
|
chars->coeff_b = 0;
|
|
}
|
|
|
|
/* ------------------------- Public API ------------------------------------- */
|
|
esp_err_t esp_adc_cal_check_efuse(esp_adc_cal_value_t source)
|
|
{
|
|
if (source != ESP_ADC_CAL_VAL_EFUSE_TP) {
|
|
return ESP_ERR_NOT_SUPPORTED;
|
|
}
|
|
uint8_t adc_encoding_version = esp_efuse_rtc_calib_get_ver();
|
|
if (adc_encoding_version != 1) {
|
|
// current version only accepts encoding ver 1.
|
|
return ESP_ERR_INVALID_VERSION;
|
|
}
|
|
return ESP_OK;
|
|
}
|
|
|
|
esp_adc_cal_value_t esp_adc_cal_characterize(adc_unit_t adc_num,
|
|
adc_atten_t atten,
|
|
adc_bits_width_t bit_width,
|
|
uint32_t default_vref,
|
|
esp_adc_cal_characteristics_t *chars)
|
|
{
|
|
esp_err_t ret;
|
|
adc_calib_parsed_info_t efuse_parsed_data = {0};
|
|
// Check parameters
|
|
ESP_RETURN_ON_FALSE(adc_num == ADC_UNIT_1 || adc_num == ADC_UNIT_2, ESP_ADC_CAL_VAL_NOT_SUPPORTED, LOG_TAG, "Invalid unit num");
|
|
ESP_RETURN_ON_FALSE(chars != NULL, ESP_ADC_CAL_VAL_NOT_SUPPORTED, LOG_TAG, "Invalid characteristic");
|
|
ESP_RETURN_ON_FALSE(bit_width == ADC_WIDTH_BIT_12, ESP_ADC_CAL_VAL_NOT_SUPPORTED, LOG_TAG, "Invalid bit_width");
|
|
ESP_RETURN_ON_FALSE(atten < SOC_ADC_ATTEN_NUM, ESP_ADC_CAL_VAL_NOT_SUPPORTED, LOG_TAG, "Invalid attenuation");
|
|
|
|
int version_num = esp_efuse_rtc_calib_get_ver();
|
|
ESP_RETURN_ON_FALSE(version_num == 1, ESP_ADC_CAL_VAL_NOT_SUPPORTED, LOG_TAG, "No calibration efuse burnt");
|
|
|
|
memset(chars, 0, sizeof(esp_adc_cal_characteristics_t));
|
|
|
|
// make sure adc is calibrated.
|
|
ret = prepare_calib_data_for(version_num, adc_num, atten, &efuse_parsed_data);
|
|
if (ret != ESP_OK) {
|
|
abort();
|
|
}
|
|
|
|
calculate_characterization_coefficients(&efuse_parsed_data, chars);
|
|
ESP_LOGD(LOG_TAG, "adc%d (atten leven %d) calibration done: A:%"PRId32" B:%"PRId32, adc_num, atten, chars->coeff_a, chars->coeff_b);
|
|
|
|
// Initialize remaining fields
|
|
chars->adc_num = adc_num;
|
|
chars->atten = atten;
|
|
chars->bit_width = bit_width;
|
|
|
|
// in esp32c3 we only use the two point method to calibrate the adc.
|
|
return ESP_ADC_CAL_VAL_EFUSE_TP;
|
|
}
|
|
|
|
uint32_t esp_adc_cal_raw_to_voltage(uint32_t adc_reading, const esp_adc_cal_characteristics_t *chars)
|
|
{
|
|
assert(chars != NULL);
|
|
|
|
int32_t error = 0;
|
|
uint64_t v_cali_1 = (uint64_t)adc_reading * chars->coeff_a / coeff_a_scaling;
|
|
esp_adc_error_calc_param_t param = {
|
|
.v_cali_input = v_cali_1,
|
|
.term_num = (chars->atten == 3) ? 5 : 3,
|
|
.coeff = &adc_error_coef_atten,
|
|
.sign = &adc_error_sign,
|
|
};
|
|
error = esp_adc_cal_get_reading_error(¶m, chars->atten);
|
|
|
|
return (int32_t)v_cali_1 - error;
|
|
}
|