Merge branch 'feat/ntc_driver_add_filter_v2.0' into 'release/v2.0'

feat(ntc_driver): improve adc result using filter (v2.0)

See merge request ae_group/esp-iot-solution!1145

README.md

@@ -109,7 +109,7 @@ The registered components in ESP-IoT-Solution are listed below:
 | [knob](https://components.espressif.com/components/espressif/knob/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/knob/versions/1.0.0) |
 | [led_indicator](https://components.espressif.com/components/espressif/led_indicator/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/led_indicator/versions/1.0.0) |
 | [lightbulb_driver](https://components.espressif.com/components/espressif/lightbulb_driver/versions/1.3.3) | [![1.3.3](https://img.shields.io/badge/Stable-1.3.3-blue)](https://components.espressif.com/components/espressif/lightbulb_driver/versions/1.3.3) |
-| [ntc_driver](https://components.espressif.com/components/espressif/ntc_driver/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/ntc_driver/versions/1.0.0) |
+| [ntc_driver](https://components.espressif.com/components/espressif/ntc_driver/versions/1.1.0) | [![1.1.0](https://img.shields.io/badge/Stable-1.1.0-blue)](https://components.espressif.com/components/espressif/ntc_driver/versions/1.1.0) |
 | [openai](https://components.espressif.com/components/espressif/openai/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/openai/versions/1.0.0) |
 | [pwm_audio](https://components.espressif.com/components/espressif/pwm_audio/versions/1.1.2) | [![1.1.2](https://img.shields.io/badge/Stable-1.1.2-blue)](https://components.espressif.com/components/espressif/pwm_audio/versions/1.1.2) |
 | [spi_bus](https://components.espressif.com/components/espressif/spi_bus/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/spi_bus/versions/1.0.0) |

README_CN.md

@@ -109,7 +109,7 @@ ESP-IoT-Solution 中注册的组件如下:
 | [knob](https://components.espressif.com/components/espressif/knob/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/knob/versions/1.0.0) |
 | [led_indicator](https://components.espressif.com/components/espressif/led_indicator/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/led_indicator/versions/1.0.0) |
 | [lightbulb_driver](https://components.espressif.com/components/espressif/lightbulb_driver/versions/1.3.3) | [![1.3.3](https://img.shields.io/badge/Stable-1.3.3-blue)](https://components.espressif.com/components/espressif/lightbulb_driver/versions/1.3.3) |
-| [ntc_driver](https://components.espressif.com/components/espressif/ntc_driver/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/ntc_driver/versions/1.0.0) |
+| [ntc_driver](https://components.espressif.com/components/espressif/ntc_driver/versions/1.1.0) | [![1.1.0](https://img.shields.io/badge/Stable-1.1.0-blue)](https://components.espressif.com/components/espressif/ntc_driver/versions/1.1.0) |
 | [openai](https://components.espressif.com/components/espressif/openai/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/openai/versions/1.0.0) |
 | [pwm_audio](https://components.espressif.com/components/espressif/pwm_audio/versions/1.1.2) | [![1.1.2](https://img.shields.io/badge/Stable-1.1.2-blue)](https://components.espressif.com/components/espressif/pwm_audio/versions/1.1.2) |
 | [spi_bus](https://components.espressif.com/components/espressif/spi_bus/versions/1.0.0) | [![1.0.0](https://img.shields.io/badge/Stable-1.0.0-blue)](https://components.espressif.com/components/espressif/spi_bus/versions/1.0.0) |

components/sensors/ntc_driver/CHANGELOG.md

@@ -1,5 +1,11 @@
 # ChangeLog
 
+## v1.1.0 - 2024-11-5
+
+### Improvements
+
+* Add NTC ADC filter to reduce the noise.
+
 ## v1.0.0 - 2024-10-15
 
 * Update the version of ntc_driver component.

components/sensors/ntc_driver/Kconfig

@@ -0,0 +1,19 @@
+menu "NTC Driver Configuration"
+
+    config ENABLE_NTC_ADC_FILTER
+        bool "Enable ADC Filter for NTC"
+        default y
+        help
+        Enable ADC Filter for NTC, the driver will take multiple ADC measurements
+        and then filters them to avoid ADC noise
+
+    config NTC_FILTER_WINDOW_SIZE
+        int "NTC Filter Window Size"
+        default 50
+        depends on ENABLE_NTC_ADC_FILTER
+        help
+        The number of ADC measurements to take before filtering the NTC value, the
+        higher the value the more stable the NTC value will be, but will take longer
+        to update
+
+endmenu

components/sensors/ntc_driver/idf_component.yml

@@ -1,4 +1,4 @@
-version: "1.0.0"
+version: "1.1.0"
 description: ntc driver
 url: https://github.com/espressif/esp-iot-solution/tree/master/components/sensors/ntc_driver
 repository: https://github.com/espressif/esp-iot-solution.git

components/sensors/ntc_driver/ntc_driver.c

@@ -183,21 +183,67 @@ static esp_err_t ntc_voltage_to_temperature(ntc_device_handle_t ntc_handle, uint
     return ESP_FAIL;
 }
 
+#ifdef CONFIG_ENABLE_NTC_ADC_FILTER
+static esp_err_t adc_oneshot_get_filtered_result(adc_oneshot_unit_handle_t handle, adc_cali_handle_t cali_handle, adc_channel_t chan, int *filtered_result)
+{
+    NTC_DRIVER_CHECK(filtered_result != NULL, "Pointer of filtered_result is invalid", ESP_FAIL);
+    int vol[CONFIG_NTC_FILTER_WINDOW_SIZE] = {0};
+    int avg = 0;
+    for (int i = 0; i < sizeof(vol) / sizeof(vol[0]); i++) {
+        int raw = 0;
+        NTC_DRIVER_CHECK(adc_oneshot_read(handle, chan, &raw) == ESP_OK, "adc oneshot read fail", ESP_FAIL);
+        ESP_LOGV(TAG, "raw: %d", raw);
+        NTC_DRIVER_CHECK(adc_cali_raw_to_voltage(cali_handle, raw, &vol[i]) == ESP_OK, "adc calibration fail", ESP_FAIL);
+        ESP_LOGV(TAG, "vol: %d", vol[i]);
+        avg += vol[i];
+    }
+    // calculate the average value
+    avg /= sizeof(vol) / sizeof(vol[0]);
+    *filtered_result = avg;
+    // calculate the standard deviation
+    int std_vol = 0;
+    for (int i = 0; i < sizeof(vol) / sizeof(vol[0]); i++) {
+        std_vol += (vol[i] - avg) * (vol[i] - avg);
+    }
+    std_vol = (int)sqrt(std_vol / (sizeof(vol) / sizeof(vol[0])));
+    // filter the result, if the difference between the value and the average value is greater than the standard deviation, the value is discarded
+    int count = 0;
+    int filtered_vol = 0;
+    for (int i = 0; i < sizeof(vol) / sizeof(vol[0]); i++) {
+        if (abs(vol[i] - avg) < std_vol) {
+            count++;
+            filtered_vol += vol[i];
+        } else {
+            ESP_LOGV(TAG, "filtered out: %d", vol[i]);
+        }
+    }
+    if (count > 0) {
+        *filtered_result = filtered_vol / count;
+    }
+
+    return ESP_OK;
+}
+#endif
+
 esp_err_t ntc_dev_get_temperature(ntc_device_handle_t ntc_handle, float *temperature)
 {
-    int voltage, adc_raw = 0;
+    int voltage = 0;
 
     if (ntc_handle == NULL) {
         ESP_LOGW(TAG, "Pointer of handle is invalid");
         return ESP_ERR_INVALID_ARG;
     }
 
     ntc_driver_dev_t *ndd = (ntc_driver_dev_t *)ntc_handle;
+#ifdef CONFIG_ENABLE_NTC_ADC_FILTER
+    esp_err_t ret = adc_oneshot_get_filtered_result(ndd->adc_handle, ndd->adc_cali_handle, ndd->s_ntc_config.channel, &voltage);
+#else
+    int adc_raw = 0;
     esp_err_t ret = adc_oneshot_read(ndd->adc_handle, ndd->s_ntc_config.channel, &adc_raw);
     NTC_DRIVER_CHECK(ret == ESP_OK, "adc oneshot read fail", ESP_FAIL);
     NTC_DRIVER_CHECK(adc_raw != 0, "adc raw data equal to 0", ESP_FAIL);
-
     ret = adc_cali_raw_to_voltage(ndd->adc_cali_handle, adc_raw, &voltage);
+#endif
     NTC_DRIVER_CHECK(ret == ESP_OK, "adc calibration raw to voltage fail", ESP_FAIL);
     NTC_DRIVER_CHECK(voltage != 0, "voltage equal to 0", ESP_FAIL);
     ntc_voltage_to_temperature(ndd, voltage, temperature);