kopia lustrzana https://github.com/espressif/esp-idf
driver/adc: support for esp32s2 adc calibration scheme
ESP32 lets the user choose from using Vref, Lookup Table, and Two-Point Calibration. In ESP32S2 only two-point calibration is supported. This commit support these changes in idf. Closes https://github.com/espressif/esp-idf/issues/5455pull/5778/head
Wu Bo Wen
rodzic
7acda7b8eb
commit
6a0951ecb2
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@ -1,3 +1,3 @@
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idf_component_register(SRC_DIRS . param_test touch_sensor_test adc_dma_test dac_dma_test
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PRIV_INCLUDE_DIRS include param_test/include touch_sensor_test/include
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PRIV_REQUIRES unity test_utils driver nvs_flash esp_serial_slave_link infrared_tools)
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PRIV_REQUIRES unity test_utils driver nvs_flash esp_serial_slave_link infrared_tools esp_adc_cal)
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@ -2,6 +2,7 @@
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Tests for the dac device driver
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*/
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#include "esp_system.h"
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#include "driver/adc.h"
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#include "driver/dac.h"
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#include "unity.h"
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@ -13,6 +14,8 @@
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#include "test_utils.h"
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#include "driver/i2s.h"
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#include "esp_adc_cal.h"
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static const char *TAG = "test_dac";
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#ifdef CONFIG_IDF_TARGET_ESP32
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@ -119,3 +122,58 @@ TEST_CASE("DAC cw generator output (RTC) check by adc", "[dac]")
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TEST_ESP_OK( dac_cw_generator_disable() );
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TEST_ESP_OK( dac_output_disable( DAC_TEST_CHANNEL_NUM ) );
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}
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#if CONFIG_IDF_TARGET_ESP32S2
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static int helper_calc_dac_output(int mV)
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{
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return mV * 0.07722;
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}
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static bool subtest_adc_dac(int mV_ref, esp_adc_cal_characteristics_t * chars)
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{
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dac_output_voltage(DAC_TEST_CHANNEL_NUM, helper_calc_dac_output(mV_ref));
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vTaskDelay(pdMS_TO_TICKS(80));
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int raw;
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adc2_get_raw((adc2_channel_t)ADC_TEST_CHANNEL_NUM, ADC_WIDTH_BIT_13, &raw);
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uint32_t voltage = esp_adc_cal_raw_to_voltage(raw, chars);
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TEST_ASSERT_INT_WITHIN( 120, mV_ref, voltage ); // 120 mV error allowance, because both DAC and ADC have error
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return true;
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}
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TEST_CASE("esp32s2 adc2-dac with adc2 calibration", "[adc-dac]")
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{
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gpio_num_t adc_gpio_num, dac_gpio_num;
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TEST_ESP_OK( adc2_pad_get_io_num( ADC_TEST_CHANNEL_NUM, &adc_gpio_num ) );
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TEST_ESP_OK( dac_pad_get_io_num( DAC_TEST_CHANNEL_NUM, &dac_gpio_num ) );
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printf("Please connect ADC2 CH%d-GPIO%d <--> DAC CH%d-GPIO%d.\n", ADC_TEST_CHANNEL_NUM, adc_gpio_num,
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DAC_TEST_CHANNEL_NUM + 1, dac_gpio_num );
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TEST_ESP_OK( dac_output_enable( DAC_TEST_CHANNEL_NUM ) );
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esp_adc_cal_characteristics_t chars;
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printf("Test 0dB atten...\n");
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adc2_config_channel_atten((adc2_channel_t)ADC_TEST_CHANNEL_NUM, ADC_ATTEN_DB_0);
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esp_adc_cal_characterize(ADC_UNIT_2, ADC_ATTEN_DB_0, ADC_WIDTH_BIT_13, 0, &chars);
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printf("a %d, b %d\n", chars.coeff_a, chars.coeff_b);
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subtest_adc_dac(750, &chars);
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printf("Test 2.5dB atten...\n");
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adc2_config_channel_atten((adc2_channel_t)ADC_TEST_CHANNEL_NUM, ADC_ATTEN_DB_2_5);
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esp_adc_cal_characterize(ADC_UNIT_2, ADC_ATTEN_DB_2_5, ADC_WIDTH_BIT_13, 0, &chars);
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printf("a %d, b %d\n", chars.coeff_a, chars.coeff_b);
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subtest_adc_dac(1100, &chars);
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printf("Test 6dB atten...\n");
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adc2_config_channel_atten((adc2_channel_t)ADC_TEST_CHANNEL_NUM, ADC_ATTEN_DB_6);
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esp_adc_cal_characterize(ADC_UNIT_2, ADC_ATTEN_DB_6, ADC_WIDTH_BIT_13, 0, &chars);
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printf("a %d, b %d\n", chars.coeff_a, chars.coeff_b);
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subtest_adc_dac(800, &chars);
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subtest_adc_dac(1250, &chars);
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printf("Test 11dB atten...\n");
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adc2_config_channel_atten((adc2_channel_t)ADC_TEST_CHANNEL_NUM, ADC_ATTEN_DB_11);
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esp_adc_cal_characterize(ADC_UNIT_2, ADC_ATTEN_DB_11, ADC_WIDTH_BIT_13, 0, &chars);
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printf("a %d, b %d\n", chars.coeff_a, chars.coeff_b);
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subtest_adc_dac(1500, &chars);
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subtest_adc_dac(2500, &chars);
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}
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#endif
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@ -1,9 +1,15 @@
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idf_build_get_property(target IDF_TARGET)
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# ToDo: re-enable adc-cal for other target
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if(NOT ${target} STREQUAL "esp32")
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return()
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if(${target} STREQUAL "esp32")
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idf_component_register(SRCS "esp_adc_cal_esp32.c"
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INCLUDE_DIRS "include"
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REQUIRES driver efuse)
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elseif(${target} STREQUAL "esp32s2")
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idf_component_register(SRCS "esp_adc_cal_esp32s2.c"
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INCLUDE_DIRS "include"
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REQUIRES driver efuse)
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endif()
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idf_component_register(SRCS "esp_adc_cal.c"
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INCLUDE_DIRS "include"
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REQUIRES driver)
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@ -1,6 +1,7 @@
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menu "ADC-Calibration"
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config ADC_CAL_EFUSE_TP_ENABLE
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depends on IDF_TARGET_ESP32
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bool "Use Two Point Values"
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default "y"
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help
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@ -9,6 +10,7 @@ menu "ADC-Calibration"
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ADC-Voltage curve using Two Point values if they are available.
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config ADC_CAL_EFUSE_VREF_ENABLE
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depends on IDF_TARGET_ESP32
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bool "Use eFuse Vref"
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default "y"
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help
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@ -17,6 +19,7 @@ menu "ADC-Calibration"
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eFuse Vref if it is available.
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config ADC_CAL_LUT_ENABLE
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depends on IDF_TARGET_ESP32
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bool "Use Lookup Tables"
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default "y"
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help
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@ -24,4 +27,5 @@ menu "ADC-Calibration"
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to correct for non-linear behavior in 11db attenuation. Other attenuations
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do not exhibit non-linear behavior hence will not be affected by this option.
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endmenu # ADC-Calibration
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@ -3,3 +3,5 @@
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#
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COMPONENT_ADD_INCLUDEDIRS := include
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COMPONENT_OBJEXCLUDE += esp_adc_cal_esp32s2.o
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@ -0,0 +1,293 @@
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// Copyright 2019-2020 Espressif Systems (Shanghai) PTE LTD
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include <stdint.h>
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#include "esp_types.h"
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#include "driver/adc.h"
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#include "soc/efuse_periph.h"
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#include "esp_err.h"
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#include "assert.h"
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#include "esp_adc_cal.h"
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#include "esp_efuse.h"
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#define ADC_CAL_CHECK(cond, ret) ({ \
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if(!(cond)){ \
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return ret; \
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} \
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})
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/* ------------------------ Characterization Constants ---------------------- */
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#define ADC_CHAR_VERSION1_EFUSEVAL 1
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static const uint32_t adc1_D_mean_low[] = {2231, 1643, 1290, 701};
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static const uint32_t adc2_D_mean_low[] = {2305, 1693, 1343, 723};
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static const uint32_t adc1_D_mean_high[] = {5775, 5692, 5725, 6209};
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static const uint32_t adc2_D_mean_high[] = {5817, 5703, 5731, 6157};
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static const int Dlow_data_length = 6;
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static const int Dhigh_data_length = 8;
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static const int adc_efuse_block = 2;
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static const int adc_calib_ver_block = 2;
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static const int adc_calib_ver_word_loc = 4;
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static const int adc_calib_ver_offset = 4;
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static const int adc_calib_ver_len = 3;
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static const int adc1_atten0_Dlow_word_loc = 6;
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static const int adc2_atten0_Dlow_word_loc = 7;
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static const int adc1_atten0_Dhigh_word_loc = 4;
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static const int adc2_atten0_Dhigh_word_loc = 5;
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static const int adc1_atten0_Dlow_offset = 16;
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static const int adc2_atten0_Dlow_offset = 8;
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static const int adc1_atten0_Dhigh_offset = 16;
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static const int adc2_atten0_Dhigh_offset = 16;
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/* ----------------------- EFuse Access Functions --------------------------- */
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/**
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* Convenience function that reads a few bits from efuse and assembles them.
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* For example, if the contents of the EFuse are:
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* Word2: 0x1234 Word3:0x5678
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* Then, setting base=2, offset=24, len=24 will yield 0x456.
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* @note does not check for boundaries, make sure parameters are correct
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* @param blk EFuse Block
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* @param base the starting word
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* @param offset the bit offset in the starting word
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* @param bit how many consecutive bits to fetch
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* @return the assembled number
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*/
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static uint32_t get_consecutive_bits_from_blk(int blk, uint32_t base, int offset, int len)
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{
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base += offset / 32;
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offset %= 32;
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if (offset + len <= 32 || base == 7) {
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uint32_t result = esp_efuse_read_reg(blk, base);
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result <<= (32 - offset - len);
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result >>= (32 - len);
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return result;
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} else {
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// need to fetch both bytes.
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uint64_t result = ((uint64_t)esp_efuse_read_reg(blk, base + 1) << 32) + esp_efuse_read_reg(blk, base);
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result &= ((uint64_t)1 << (offset + len)) - 1;
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result >>= offset;
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return result;
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}
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}
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/**
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* To save space in EFuse, the calibration values for adc are compressed.
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* The compression scheme is: for X bits of ADC Efuse data,
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* The actual ADC reading is: BASE_VALUE + 4*ADC_OFFSET
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* where ADC_OFFSET = bits X-1:0 in Efuse, the highest bit is the sign bit (0:+, 1:-).
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*
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* The following functions do this conversion.
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* @param efuse_val raw values read from efuse.
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* @param adc_num Specifies the channel number. The 2 adc channels each have different calibration values.
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* @param attem Specifies the attenuation. Different attenuation level have different calibration values.
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*/
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static uint32_t efuse_low_val_to_d(uint16_t efuse_val, adc_unit_t adc_num, adc_atten_t atten)
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{
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// efuse_val is 5 bits + 6th sign bit.
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int32_t rawoffsetval = efuse_val & ((1 << (Dlow_data_length - 1)) - 1);
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// if the sign bit is 1, it means it is a negative sign.
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int32_t offset = (efuse_val & (1 << (Dlow_data_length - 1))) ? (-rawoffsetval * 4) : (rawoffsetval * 4);
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if (adc_num == ADC_UNIT_1) {
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return offset + adc1_D_mean_low[atten - ADC_ATTEN_DB_0];
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} else {
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return offset + adc2_D_mean_low[atten - ADC_ATTEN_DB_0];
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}
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}
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static uint32_t efuse_high_val_to_d (uint16_t efuse_val, adc_unit_t adc_num, adc_atten_t atten)
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{
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// efuse_val is 7 bits + 8th sign bit.
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int32_t rawoffsetval = efuse_val & ((1 << (Dhigh_data_length - 1)) - 1);
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int32_t offset = (efuse_val & (1 << (Dhigh_data_length - 1))) ? (-rawoffsetval * 4) : (rawoffsetval * 4);
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if (adc_num == ADC_UNIT_1) {
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return offset + adc1_D_mean_high[atten - ADC_ATTEN_DB_0];
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} else {
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return offset + adc2_D_mean_high[atten - ADC_ATTEN_DB_0];
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}
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}
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/**
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* To save space in EFuse, the calibration values for adc are compressed.
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* The compression scheme is: for X bits of ADC Efuse data,
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* The actual ADC reading is: BASE_VALUE + 4*ADC_OFFSET
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* where ADC_OFFSET = bits X-1:0 in Efuse, the highest bit is the sign bit (0:+, 1:-).
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*
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* The following functions do the reading.
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* @param efuse_val raw values read from efuse.
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* @param adc_num Specifies the channel number. The 2 adc channels each have different calibration values.
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* @param attem Specifies the attenuation. Different attenuation level have different calibration values.
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*/
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static uint32_t read_efuse_tp_low(adc_unit_t adc_num, adc_atten_t atten)
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{
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// this fcn retrieves and decodes the calibration value stored in efuse.
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uint32_t base;
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int offset;
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// may need to move magic numbers out
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if (adc_num == ADC_UNIT_1) {
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// the first value is at the 16th bit of the 6th word of the efuse block 2, each value is 6 bits long.
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base = adc1_atten0_Dlow_word_loc;
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offset = adc1_atten0_Dlow_offset + Dlow_data_length * (atten - ADC_ATTEN_DB_0);
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} else {
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// the first value is at the 8th bit of the 7th word of the efuse block 2, each value is 6 bits long.
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base = adc2_atten0_Dlow_word_loc;
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offset = adc2_atten0_Dlow_offset + Dlow_data_length * (atten - ADC_ATTEN_DB_0);
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}
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uint32_t read_result = get_consecutive_bits_from_blk(adc_efuse_block, base, offset, Dlow_data_length);
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return read_result;
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}
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static uint32_t read_efuse_tp_high(adc_unit_t adc_num, adc_atten_t atten)
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{
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// this fcn retrieves and decodes the calibration value stored in efuse.
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uint32_t base;
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int offset;
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if (adc_num == ADC_UNIT_1) {
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// the first value is at the 16th bit of the 4th word of the efuse block 2, each value is 8 bits long.
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base = adc1_atten0_Dhigh_word_loc;
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offset = adc1_atten0_Dhigh_offset + Dhigh_data_length * (atten - ADC_ATTEN_DB_0);
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} else {
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// the first value is at the 16th bit of the 5th word of the efuse block 2, each value is 8 bits long.
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base = adc2_atten0_Dhigh_word_loc;
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offset = adc2_atten0_Dhigh_offset + Dhigh_data_length * (atten - ADC_ATTEN_DB_0);
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}
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uint32_t read_result = get_consecutive_bits_from_blk(adc_efuse_block, base, offset, Dhigh_data_length);
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return read_result;
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}
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/* ----------------------- Characterization Functions ----------------------- */
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// coeff_a and coeff_b are actually floats
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// they are scaled to put them into uint32_t so that the headers do not have to be changed
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static const int coeff_a_scaling = 65536;
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static const int coeff_b_scaling = 1024;
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/**
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* The Two Point calibration measures the reading at two specific input voltages, and calculates the (assumed linear) relation
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* between input voltage and ADC response. (Response = A * Vinput + B)
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* A and B are scaled ints.
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* @param high The ADC response at the higher voltage of the corresponding attenuation (600mV, 800mV, 1000mV, 2000mV).
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* @param low The ADC response at the lower voltage of the corresponding attenuation (all 250mV).
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*
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*/
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static void characterize_using_two_point(adc_unit_t adc_num,
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adc_atten_t atten,
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uint32_t high,
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uint32_t low,
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uint32_t *coeff_a,
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uint32_t *coeff_b)
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{
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// once we have recovered the reference high(Dhigh) and low(Dlow) readings, we can calculate a and b from
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// the measured high and low readings
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static const uint32_t v_high[] = {600, 800, 1000, 2000};
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static const uint32_t v_low = 250;
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*coeff_a = coeff_a_scaling * (v_high[atten] - v_low) / (high - low);
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*coeff_b = coeff_b_scaling * (v_low * high - v_high[atten] * low) / (high - low);
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}
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/* ------------------------- Public API ------------------------------------- */
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esp_err_t esp_adc_cal_check_efuse(esp_adc_cal_value_t source)
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{
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if (source != ESP_ADC_CAL_VAL_EFUSE_TP) {
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return ESP_ERR_NOT_SUPPORTED;
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}
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uint8_t adc1_atten0_dh = get_consecutive_bits_from_blk(adc_efuse_block, adc1_atten0_Dhigh_word_loc, adc1_atten0_Dhigh_offset, Dhigh_data_length);
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uint8_t adc2_atten0_dh = get_consecutive_bits_from_blk(adc_efuse_block, adc2_atten0_Dhigh_word_loc, adc2_atten0_Dhigh_offset, Dhigh_data_length);
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if (!adc1_atten0_dh || !adc2_atten0_dh) {
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return ESP_ERR_NOT_SUPPORTED;
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}
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uint8_t adc_encoding_version = get_consecutive_bits_from_blk(adc_calib_ver_block, adc_calib_ver_word_loc, adc_calib_ver_offset, adc_calib_ver_len);
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if (adc_encoding_version != 1) {
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// current version only accepts encoding ver 1.
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return ESP_ERR_INVALID_VERSION;
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}
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return ESP_OK;
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}
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esp_adc_cal_value_t esp_adc_cal_characterize(adc_unit_t adc_num,
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adc_atten_t atten,
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adc_bits_width_t bit_width,
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uint32_t default_vref,
|
||||
esp_adc_cal_characteristics_t *chars)
|
||||
{
|
||||
// Check parameters
|
||||
assert((adc_num == ADC_UNIT_1) || (adc_num == ADC_UNIT_2));
|
||||
assert(chars != NULL);
|
||||
assert(bit_width == ADC_WIDTH_BIT_13);
|
||||
|
||||
// Characterize based on efuse Two Point values. If these values are not present in efuse,
|
||||
// or efuse values are of a version that we do not recognize, automatically assume default values.
|
||||
uint32_t adc_calib_high, adc_calib_low;
|
||||
if (esp_adc_cal_check_efuse(ESP_ADC_CAL_VAL_EFUSE_TP) == ESP_OK) {
|
||||
adc_calib_high = read_efuse_tp_high(adc_num, atten);
|
||||
adc_calib_low = read_efuse_tp_low(adc_num, atten);
|
||||
} else {
|
||||
adc_calib_high = 0;
|
||||
adc_calib_low = 0;
|
||||
}
|
||||
uint32_t high = efuse_high_val_to_d(adc_calib_high, adc_num, atten);
|
||||
uint32_t low = efuse_low_val_to_d(adc_calib_low, adc_num, atten);
|
||||
characterize_using_two_point(adc_num, atten, high, low, &(chars->coeff_a), &(chars->coeff_b));
|
||||
// Initialize remaining fields
|
||||
chars->adc_num = adc_num;
|
||||
chars->atten = atten;
|
||||
chars->bit_width = bit_width;
|
||||
|
||||
// these values are not used as the corresponding calibration themes are deprecated.
|
||||
chars->vref = 0;
|
||||
chars->low_curve = NULL;
|
||||
chars->high_curve = NULL;
|
||||
|
||||
// in esp32s2 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)
|
||||
{
|
||||
ADC_CAL_CHECK(chars != NULL, ESP_ERR_INVALID_ARG);
|
||||
|
||||
return adc_reading * chars->coeff_a / coeff_a_scaling + chars->coeff_b / coeff_b_scaling;
|
||||
}
|
||||
|
||||
esp_err_t esp_adc_cal_get_voltage(adc_channel_t channel,
|
||||
const esp_adc_cal_characteristics_t *chars,
|
||||
uint32_t *voltage)
|
||||
{
|
||||
// Check parameters
|
||||
ADC_CAL_CHECK(chars != NULL, ESP_ERR_INVALID_ARG);
|
||||
ADC_CAL_CHECK(voltage != NULL, ESP_ERR_INVALID_ARG);
|
||||
|
||||
int adc_reading;
|
||||
if (chars->adc_num == ADC_UNIT_1) {
|
||||
//Check if channel is valid on ADC1
|
||||
ADC_CAL_CHECK((adc1_channel_t)channel < ADC1_CHANNEL_MAX, ESP_ERR_INVALID_ARG);
|
||||
adc_reading = adc1_get_raw(channel);
|
||||
} else {
|
||||
//Check if channel is valid on ADC2
|
||||
ADC_CAL_CHECK((adc2_channel_t)channel < ADC2_CHANNEL_MAX, ESP_ERR_INVALID_ARG);
|
||||
if (adc2_get_raw(channel, chars->bit_width, &adc_reading) != ESP_OK) {
|
||||
return ESP_ERR_TIMEOUT; //Timed out waiting for ADC2
|
||||
}
|
||||
}
|
||||
*voltage = esp_adc_cal_raw_to_voltage((uint32_t)adc_reading, chars);
|
||||
return ESP_OK;
|
||||
}
|
||||
|
||||
|
|
@ -30,6 +30,7 @@ typedef enum {
|
|||
ESP_ADC_CAL_VAL_EFUSE_VREF = 0, /**< Characterization based on reference voltage stored in eFuse*/
|
||||
ESP_ADC_CAL_VAL_EFUSE_TP = 1, /**< Characterization based on Two Point values stored in eFuse*/
|
||||
ESP_ADC_CAL_VAL_DEFAULT_VREF = 2, /**< Characterization based on default reference voltage*/
|
||||
ESP_ADC_CAL_VAL_MAX
|
||||
} esp_adc_cal_value_t;
|
||||
|
||||
/**
|
||||
|
|
@ -71,12 +72,15 @@ esp_err_t esp_adc_cal_check_efuse(esp_adc_cal_value_t value_type);
|
|||
* Characterization can be based on Two Point values, eFuse Vref, or default Vref
|
||||
* and the calibration values will be prioritized in that order.
|
||||
*
|
||||
* @note Two Point values and eFuse Vref can be enabled/disabled using menuconfig.
|
||||
* @note
|
||||
* For ESP32, Two Point values and eFuse Vref calibration can be enabled/disabled using menuconfig.
|
||||
* For ESP32s2, only Two Point values calibration and only ADC_WIDTH_BIT_13 is supported. The parameter default_vref is unused.
|
||||
*
|
||||
*
|
||||
* @param[in] adc_num ADC to characterize (ADC_UNIT_1 or ADC_UNIT_2)
|
||||
* @param[in] atten Attenuation to characterize
|
||||
* @param[in] bit_width Bit width configuration of ADC
|
||||
* @param[in] default_vref Default ADC reference voltage in mV (used if eFuse values is not available)
|
||||
* @param[in] default_vref Default ADC reference voltage in mV (Only in ESP32, used if eFuse values is not available)
|
||||
* @param[out] chars Pointer to empty structure used to store ADC characteristics
|
||||
*
|
||||
* @return
|
||||
|
|
|
|||
|
|
@ -12,15 +12,13 @@
|
|||
#include "freertos/task.h"
|
||||
#include "driver/gpio.h"
|
||||
#include "driver/adc.h"
|
||||
#if CONFIG_IDF_TARGET_ESP32
|
||||
#include "esp_adc_cal.h"
|
||||
#endif
|
||||
|
||||
#define DEFAULT_VREF 1100 //Use adc2_vref_to_gpio() to obtain a better estimate
|
||||
#define NO_OF_SAMPLES 64 //Multisampling
|
||||
|
||||
#if CONFIG_IDF_TARGET_ESP32
|
||||
static esp_adc_cal_characteristics_t *adc_chars;
|
||||
#if CONFIG_IDF_TARGET_ESP32
|
||||
static const adc_channel_t channel = ADC_CHANNEL_6; //GPIO34 if ADC1, GPIO14 if ADC2
|
||||
static const adc_bits_width_t width = ADC_WIDTH_BIT_12;
|
||||
#elif CONFIG_IDF_TARGET_ESP32S2
|
||||
|
|
@ -30,23 +28,33 @@ static const adc_bits_width_t width = ADC_WIDTH_BIT_13;
|
|||
static const adc_atten_t atten = ADC_ATTEN_DB_0;
|
||||
static const adc_unit_t unit = ADC_UNIT_1;
|
||||
|
||||
#if CONFIG_IDF_TARGET_ESP32
|
||||
|
||||
static void check_efuse(void)
|
||||
{
|
||||
//Check TP is burned into eFuse
|
||||
#if CONFIG_IDF_TARGET_ESP32
|
||||
//Check if TP is burned into eFuse
|
||||
if (esp_adc_cal_check_efuse(ESP_ADC_CAL_VAL_EFUSE_TP) == ESP_OK) {
|
||||
printf("eFuse Two Point: Supported\n");
|
||||
} else {
|
||||
printf("eFuse Two Point: NOT supported\n");
|
||||
}
|
||||
|
||||
//Check Vref is burned into eFuse
|
||||
if (esp_adc_cal_check_efuse(ESP_ADC_CAL_VAL_EFUSE_VREF) == ESP_OK) {
|
||||
printf("eFuse Vref: Supported\n");
|
||||
} else {
|
||||
printf("eFuse Vref: NOT supported\n");
|
||||
}
|
||||
#elif CONFIG_IDF_TARGET_ESP32S2
|
||||
if (esp_adc_cal_check_efuse(ESP_ADC_CAL_VAL_EFUSE_TP) == ESP_OK) {
|
||||
printf("eFuse Two Point: Supported\n");
|
||||
} else {
|
||||
printf("Cannot retrieve eFuse Two Point calibration values. Default calibration values will be used.\n");
|
||||
}
|
||||
#else
|
||||
#error "This example is configured for ESP32/ESP32S2."
|
||||
#endif
|
||||
}
|
||||
|
||||
|
||||
static void print_char_val_type(esp_adc_cal_value_t val_type)
|
||||
{
|
||||
|
|
@ -58,14 +66,12 @@ static void print_char_val_type(esp_adc_cal_value_t val_type)
|
|||
printf("Characterized using Default Vref\n");
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
||||
|
||||
void app_main(void)
|
||||
{
|
||||
#if CONFIG_IDF_TARGET_ESP32
|
||||
//Check if Two Point or Vref are burned into eFuse
|
||||
check_efuse();
|
||||
#endif
|
||||
|
||||
//Configure ADC
|
||||
if (unit == ADC_UNIT_1) {
|
||||
|
|
@ -75,12 +81,10 @@ void app_main(void)
|
|||
adc2_config_channel_atten((adc2_channel_t)channel, atten);
|
||||
}
|
||||
|
||||
#if CONFIG_IDF_TARGET_ESP32
|
||||
//Characterize ADC
|
||||
adc_chars = calloc(1, sizeof(esp_adc_cal_characteristics_t));
|
||||
esp_adc_cal_value_t val_type = esp_adc_cal_characterize(unit, atten, width, DEFAULT_VREF, adc_chars);
|
||||
print_char_val_type(val_type);
|
||||
#endif
|
||||
|
||||
//Continuously sample ADC1
|
||||
while (1) {
|
||||
|
|
@ -96,13 +100,9 @@ void app_main(void)
|
|||
}
|
||||
}
|
||||
adc_reading /= NO_OF_SAMPLES;
|
||||
#if CONFIG_IDF_TARGET_ESP32
|
||||
//Convert adc_reading to voltage in mV
|
||||
uint32_t voltage = esp_adc_cal_raw_to_voltage(adc_reading, adc_chars);
|
||||
printf("Raw: %d\tVoltage: %dmV\n", adc_reading, voltage);
|
||||
#elif CONFIG_IDF_TARGET_ESP32S2
|
||||
printf("ADC%d CH%d Raw: %d\t\n", unit, channel, adc_reading);
|
||||
#endif
|
||||
vTaskDelay(pdMS_TO_TICKS(1000));
|
||||
}
|
||||
}
|
||||
|
|
|
|||
|
|
@ -45,7 +45,7 @@ void app_main(void)
|
|||
|
||||
//be sure to do the init before using adc2.
|
||||
printf("adc2_init...\n");
|
||||
adc2_config_channel_atten( ADC2_EXAMPLE_CHANNEL, ADC_ATTEN_0db );
|
||||
adc2_config_channel_atten( ADC2_EXAMPLE_CHANNEL, ADC_ATTEN_11db );
|
||||
|
||||
vTaskDelay(2 * portTICK_PERIOD_MS);
|
||||
|
||||
|
|
|
|||
Ładowanie…
Reference in New Issue