esp-idf/components/esp_adc/esp32p4/curve_fitting_coefficients.c

89 lines
3.2 KiB
C

/*
* SPDX-FileCopyrightText: 2024-2025 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <stdio.h>
#include <stdint.h>
#include "esp_efuse_rtc_calib.h"
#include "../curve_fitting_coefficients.h"
#define COEFF_VERSION_NUM 1 // Currently P4 has one versions of curve calibration schemes
#define COEFF_GROUP_NUM 4
#define TERM_MAX 2
/**
* @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 ~ 3, error = (K0 * X^0) + (K1 * X^1)
* @note Above formula is rewritten from the original documentation, please note that the coefficients are re-ordered.
*/
const static uint64_t adc1_error_coef_atten[COEFF_VERSION_NUM][COEFF_GROUP_NUM][TERM_MAX][2] = {
/* Coefficients of calibration version 1 */
{
{{7170501832480995, 1e16}, {10598497992115, 1e16}}, //atten0
{{9960085535084866, 1e16}, {15840076608145, 1e16}}, //atten1
{{14711053224678996, 1e16}, {1594266424857, 1e17}}, //atten2
{{28811493455181565, 1e16}, {10082311568625, 1e16}}, //atten3
},
};
const static uint64_t adc2_error_coef_atten[COEFF_VERSION_NUM][COEFF_GROUP_NUM][TERM_MAX][2] = {
/* Coefficients of calibration version 1 */
{
{{4900967548489932, 1e16}, {5037402667913, 1e16}}, //atten0
{{7296214814536025, 1e16}, {11021577596635, 1e16}}, //atten1
{{10991620450220592, 1e16}, {11623930881896, 1e16}}, //atten2
{{24421401024626730, 1e16}, {9458501263393, 1e16}}, //atten3
},
};
/**
* Term sign ADC1
*/
const static int32_t adc1_error_sign[COEFF_VERSION_NUM][COEFF_GROUP_NUM][TERM_MAX] = {
/* Coefficient sign of calibration version 1 */
{
{-1, 1}, //atten0
{-1, 1}, //atten1
{-1, 1}, //atten2
{-1, 1}, //atten3
},
};
/**
* Term sign ADC2
*/
const static int32_t adc2_error_sign[COEFF_VERSION_NUM][COEFF_GROUP_NUM][TERM_MAX] = {
/* Coefficient sign of calibration version 1 */
{
{-1, 1}, //atten0
{-1, 1}, //atten1
{-1, 1}, //atten2
{-1, 1}, //atten3
},
};
void curve_fitting_get_second_step_coeff(const adc_cali_curve_fitting_config_t *config, cali_chars_second_step_t *ctx)
{
uint32_t adc_calib_ver = esp_efuse_rtc_calib_get_ver();
assert((adc_calib_ver >= ESP_EFUSE_ADC_CALIB_VER_MIN) &&
(adc_calib_ver <= ESP_EFUSE_ADC_CALIB_VER_MAX));
ctx->term_num = 2;
ctx->coeff = config->unit_id == ADC_UNIT_1 ?
adc1_error_coef_atten[VER2IDX(adc_calib_ver)][config->atten] :
adc2_error_coef_atten[VER2IDX(adc_calib_ver)][config->atten];
ctx->sign = config->unit_id == ADC_UNIT_1 ?
adc1_error_sign[VER2IDX(adc_calib_ver)][config->atten] :
adc2_error_sign[VER2IDX(adc_calib_ver)][config->atten];
}