1 /*
2 * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 #include <stdio.h>
8 #include <stdint.h>
9 #include "esp_efuse_rtc_calib.h"
10 #include "../curve_fitting_coefficients.h"
11
12 #define COEFF_VERSION_NUM 1 // Currently H2 has one versions of curve calibration schemes
13
14 /**
15 * @note Error Calculation
16 * Coefficients for calculating the reading voltage error.
17 * Four sets of coefficients for atten0 ~ atten3 respectively.
18 *
19 * For each item, first element is the Coefficient, second element is the Multiple. (Coefficient / Multiple) is the real coefficient.
20 *
21 * @note {0,0} stands for unused item
22 * @note In case of the overflow, these coefficients are recorded as Absolute Value
23 * @note For atten0 ~ 2, error = (K0 * X^0) + (K1 * X^1)
24 * @note For atten3, error = (K0 * X^0) + (K1 * X^1) + (K2 * X^2)
25 * @note Above formula is rewritten from the original documentation, please note that the coefficients are re-ordered.
26 */
27 const static uint64_t adc1_error_coef_atten[COEFF_VERSION_NUM][COEFF_GROUP_NUM][TERM_MAX][2] = {
28 /* Coefficients of calibration version 1 */
29 {
30 {{5081991760658888, 1e16}, {7858995318513, 1e19}, {0, 1}, {0, 0}, {0, 0}}, //atten0
31 {{8359230818901277, 1e16}, {9025419089179, 1e19}, {0, 1}, {0, 0}, {0, 0}}, //atten1
32 {{1165668771581976, 1e15}, {8294679249061, 1e19}, {0, 1}, {0, 0}, {0, 0}}, //atten2
33 {{3637329628677273, 1e16}, {19607259738935, 1e18}, {7871689227, 1e16}, {0, 0}, {0, 0}}, //atten3
34 },
35 };
36
37 /**
38 * Term sign
39 */
40 const static int32_t adc1_error_sign[COEFF_VERSION_NUM][COEFF_GROUP_NUM][TERM_MAX] = {
41 /* Coefficient sign of calibration version 1 */
42 {
43 {-1, 1, 1, 0, 0}, //atten0
44 {-1, 1, 1, 0, 0}, //atten1
45 {-1, 1, 1, 0, 0}, //atten2
46 {-1, -1, 1, 0, 0}, //atten3
47 },
48 };
49
curve_fitting_get_second_step_coeff(const adc_cali_curve_fitting_config_t * config,cali_chars_second_step_t * ctx)50 void curve_fitting_get_second_step_coeff(const adc_cali_curve_fitting_config_t *config, cali_chars_second_step_t *ctx)
51 {
52 uint32_t adc_calib_ver = esp_efuse_rtc_calib_get_ver();
53 assert((adc_calib_ver >= ESP_EFUSE_ADC_CALIB_VER_MIN) &&
54 (adc_calib_ver <= ESP_EFUSE_ADC_CALIB_VER_MAX));
55
56 ctx->term_num = 3;
57 ctx->coeff = &adc1_error_coef_atten[VER2IDX(adc_calib_ver)];
58 ctx->sign = &adc1_error_sign[VER2IDX(adc_calib_ver)];
59 }
60
