kopia lustrzana https://github.com/espressif/esp-idf
50 wiersze
2.2 KiB
C
50 wiersze
2.2 KiB
C
/*
|
|
* SPDX-FileCopyrightText: 2019-2023 Espressif Systems (Shanghai) CO LTD
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0
|
|
*/
|
|
|
|
#include <stdint.h>
|
|
#include "../curve_fitting_coefficients.h"
|
|
|
|
#define COEFF_GROUP_NUM 4
|
|
#define TERM_MAX 5
|
|
|
|
/**
|
|
* @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 adc1_error_coef_atten[COEFF_GROUP_NUM][TERM_MAX][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
|
|
*/
|
|
const static int32_t adc1_error_sign[COEFF_GROUP_NUM][TERM_MAX] = {
|
|
{-1, -1, 1, 0, 0}, //atten0
|
|
{ 1, -1, 1, 0, 0}, //atten1
|
|
{-1, -1, 1, 0, 0}, //atten2
|
|
{-1, -1, 1, -1, 1} //atten3
|
|
};
|
|
|
|
void curve_fitting_get_second_step_coeff(const adc_cali_curve_fitting_config_t *config, cali_chars_second_step_t *ctx)
|
|
{
|
|
ctx->term_num = (config->atten == 3) ? 5 : 3;
|
|
// On esp32c3, ADC1 and ADC2 share the second step coefficients
|
|
// And if the target only has 1 ADC peripheral, just use the ADC1 directly
|
|
ctx->coeff = adc1_error_coef_atten[config->atten];
|
|
ctx->sign = adc1_error_sign[config->atten];
|
|
}
|