add ledc

.gitmodules

@@ -1,6 +1,8 @@
 [submodule "components/esp32-owb"]
     path = components/esp32-owb
-    url = ../esp32-owb
+    url = https://github.com/DavidAntliff/esp32-owb.git
+    branch = master
 [submodule "components/esp32-ds18b20"]
     path = components/esp32-ds18b20
-    url = ../esp32-ds18b20
+    url = https://github.com/DavidAntliff/esp32-ds18b20.git
+    branch = master

.travis.yml

@@ -1,37 +0,0 @@
-os: linux
-dist: bionic
-language: python
-python: "3.8"
-
-jobs:
-  include:
-    - stage:  # IDF v3.3
-      install:
-        # Install ESP32 toochain following steps as described
-        # in http://esp-idf.readthedocs.io/en/latest/linux-setup.html
-        #
-        # Download binary toolchain for the ESP32
-        - pushd ~
-        - wget https://dl.espressif.com/dl/xtensa-esp32-elf-linux64-1.22.0-80-g6c4433a-5.2.0.tar.gz
-        - tar -xzf xtensa-esp32-elf-linux64-1.22.0-80-g6c4433a-5.2.0.tar.gz
-        # Make xtensa-esp32-elf available for all terminal sessions
-        - export PATH=$PATH:$(pwd)/xtensa-esp32-elf/bin
-        # Get ESP-IDF from github
-        - git clone --recursive --branch v3.3 --single-branch --shallow-submodules https://github.com/espressif/esp-idf.git esp-idf
-        # Set the path to ESP-IDF directory
-        - export IDF_PATH=$(pwd)/esp-idf
-        # Install python dependencies
-        - pip install --requirement $IDF_PATH/requirements.txt
-        - popd
-      script:
-        - $IDF_PATH/tools/idf.py build
-
-    - stage:  # IDF v4.1-beta1
-      install:
-        - pushd ~
-        - git clone --recursive --branch v4.1-beta1 --single-branch --shallow-submodules https://github.com/espressif/esp-idf.git esp-idf
-        - esp-idf/install.sh
-        - popd
-      script:
-        - source ~/esp-idf/export.sh && idf.py build
-

README.md

@@ -1,26 +1,17 @@
-# esp32-ds18b20-example
+# esp32-ds18b20-ledc
-
-[![Platform: ESP-IDF](https://img.shields.io/badge/ESP--IDF-v3.0%2B-blue.svg)](https://docs.espressif.com/projects/esp-idf/en/stable/get-started/)
-[![Build Status](https://travis-ci.org/DavidAntliff/esp32-ds18b20-example.svg?branch=master)](https://travis-ci.org/DavidAntliff/esp32-ds18b20-example)
-[![license](https://img.shields.io/github/license/mashape/apistatus.svg)]()
 
 ## Introduction
 
 This is an example application for the Maxim Integrated DS18B20 Programmable Resolution 1-Wire Digital Thermometer 
-device.
+device and LEDs.
-
-It supports a single or multiple devices on the same 1-Wire bus.
-
-It is written and tested for v3.3 and v4.1-beta1 of the [ESP-IDF](https://github.com/espressif/esp-idf) environment,
-using the xtensa-esp32-elf toolchain (gcc version 5.2.0, crosstool-ng-1.22.0-80-g6c4433a).
 
 Ensure that submodules are cloned:
 
-    $ git clone --recursive https://github.com/DavidAntliff/esp32-ds18b20-example.git
+    $ git clone --recursive https://github.com/nmasse-itix/esp32-ds18b20-ledc.git
 
 Build the application with:
 
-    $ cd esp32-ds18b20-example
+    $ cd esp32-ds18b20-ledc
     $ idf.py menuconfig    # set your serial configuration and the 1-Wire GPIO - see below
     $ idf.py build
     $ idf.py -p (PORT) flash monitor
@@ -42,43 +33,7 @@ resistor of 4.7 KOhms, connected to the 3.3V supply.
 
 `idf.py menuconfig` can be used to set the 1-Wire GPIO.
 
-If you have several devices and see occasional CRC errors, consider using a 2.2 kOhm pull-up resistor instead. Also 
+Connect two leds on GPIO 19 and 21 with a small resistor (69 ohms).
-consider adding decoupling capacitors between the sensor supply voltage and ground, as close to each sensor as possible.
-
-If you wish to enable a second GPIO to control an external strong pull-up circuit for parasitic power mode, ensure 
-`CONFIG_ENABLE_STRONG_PULLUP=y` and `CONFIG_STRONG_PULLUP_GPIO` is set appropriately.
- 
-See documentation for [esp32-ds18b20](https://www.github.com/DavidAntliff/esp32-ds18b20-example#parasitic-power-mode)
-for further information about parasitic power mode, including strong pull-up configuration.
-
-
-## Features
-
-This example provides:
-
- * External power supply detection.
- * Parasitic power supply detection.
- * Static (stack-based) or dynamic (malloc-based) memory model examples.
- * No global variables.
- * Device search.
- * Addressing optimisation for a single (solo) device on a bus.
- * CRC checks on ROM code and temperature data.
- * Programmable temperature measurement resolution (9, 10, 11 or 12-bit resolution).
- * Temperature conversion and retrieval.
- * Simultaneous conversion across multiple devices.
-
-## Source Code
-
-The source is available from [GitHub](https://www.github.com/DavidAntliff/esp32-ds18b20-example).
-
-## License
-
-The code in this project is licensed under the MIT license - see LICENSE for details.
-
-## Links
-
- * [DS18B20 Datasheet](http://datasheets.maximintegrated.com/en/ds/DS18B20.pdf)
- * [Espressif IoT Development Framework for ESP32](https://github.com/espressif/esp-idf)
 
 ## Acknowledgements
 

main/app_main.c

@@ -27,6 +27,9 @@
 #include "esp_system.h"
 #include "esp_log.h"
 
+#include "driver/gpio.h"
+#include "driver/ledc.h"
+
 #include "owb.h"
 #include "owb_rmt.h"
 #include "ds18b20.h"
@@ -36,6 +39,57 @@
 #define DS18B20_RESOLUTION   (DS18B20_RESOLUTION_12_BIT)
 #define SAMPLE_PERIOD        (1000)   // milliseconds
 
+static void led_task(void *pvParameters) {
+    // Prepare and then apply the LEDC PWM timer configuration
+    ledc_timer_config_t ledc_timer_0 = {
+        .speed_mode       = LEDC_HIGH_SPEED_MODE,
+        .timer_num        = LEDC_TIMER_0,
+        .duty_resolution  = LEDC_TIMER_8_BIT,
+        .freq_hz          = 1000,  // Set output frequency at 5 kHz
+        .clk_cfg          = LEDC_AUTO_CLK
+    };
+    ESP_ERROR_CHECK(ledc_timer_config(&ledc_timer_0));
+
+    // Prepare and then apply the LEDC PWM channel configuration
+    ledc_channel_config_t ledc_channel_1 = {
+        .speed_mode     = LEDC_HIGH_SPEED_MODE,
+        .channel        = LEDC_CHANNEL_0,
+        .timer_sel      = LEDC_TIMER_0,
+        .intr_type      = LEDC_INTR_DISABLE,
+        .gpio_num       = GPIO_NUM_19,
+        .duty           = 0, // Set duty to 0%
+        .hpoint         = 0
+    };
+    ledc_channel_config_t ledc_channel_2 = {
+        .speed_mode     = LEDC_HIGH_SPEED_MODE,
+        .channel        = LEDC_CHANNEL_1,
+        .timer_sel      = LEDC_TIMER_0,
+        .intr_type      = LEDC_INTR_DISABLE,
+        .gpio_num       = GPIO_NUM_21,
+        .duty           = 0, // Set duty to 0%
+        .hpoint         = 0
+    };
+    ESP_ERROR_CHECK(ledc_channel_config(&ledc_channel_1));
+    ESP_ERROR_CHECK(ledc_channel_config(&ledc_channel_2));
+
+    int steps[] = {
+        0, 16, 32, 48, 64, 80, 96, 112, 128, 128, 112, 96, 80, 64, 48, 32, 16, 0
+    };
+    int n_steps = sizeof(steps) / sizeof(steps[0]);
+    for (;;) {
+        for (int i = 0; i < n_steps; i++) {
+            // Wait 10s and update the duty cycle
+            vTaskDelay(100.0 / portTICK_PERIOD_MS);
+            ESP_ERROR_CHECK(ledc_set_duty(LEDC_HIGH_SPEED_MODE, LEDC_CHANNEL_0, steps[i]));
+            ESP_ERROR_CHECK(ledc_set_duty(LEDC_HIGH_SPEED_MODE, LEDC_CHANNEL_1, steps[(i+4)%n_steps]));
+            ESP_ERROR_CHECK(ledc_update_duty(LEDC_HIGH_SPEED_MODE, LEDC_CHANNEL_0));
+            ESP_ERROR_CHECK(ledc_update_duty(LEDC_HIGH_SPEED_MODE, LEDC_CHANNEL_1));
+        }
+    }
+
+    vTaskDelete(NULL);
+}
+
 _Noreturn void app_main()
 {
     // Override global log level
@@ -45,6 +99,18 @@ _Noreturn void app_main()
     //esp_log_level_set("owb", ESP_LOG_DEBUG);
     //esp_log_level_set("ds18b20", ESP_LOG_DEBUG);
 
+    BaseType_t xReturned;
+    xReturned = xTaskCreate(led_task,
+                            "led_task",
+                            4096,           /* Stack size in words, not bytes. */
+                            NULL,           /* Parameter passed into the task. */
+                            tskIDLE_PRIORITY + 12,
+                            NULL);
+    if (xReturned != pdPASS) {
+        ESP_LOGE("led", "xTaskCreate('led_task'): %d", xReturned);
+        abort();
+    }
+
     // Stable readings require a brief period before communication
     vTaskDelay(2000.0 / portTICK_PERIOD_MS);
 
@@ -72,50 +138,6 @@ _Noreturn void app_main()
     }
     printf("Found %d device%s\n", num_devices, num_devices == 1 ? "" : "s");
 
-    // In this example, if a single device is present, then the ROM code is probably
-    // not very interesting, so just print it out. If there are multiple devices,
-    // then it may be useful to check that a specific device is present.
-
-    if (num_devices == 1)
-    {
-        // For a single device only:
-        OneWireBus_ROMCode rom_code;
-        owb_status status = owb_read_rom(owb, &rom_code);
-        if (status == OWB_STATUS_OK)
-        {
-            char rom_code_s[OWB_ROM_CODE_STRING_LENGTH];
-            owb_string_from_rom_code(rom_code, rom_code_s, sizeof(rom_code_s));
-            printf("Single device %s present\n", rom_code_s);
-        }
-        else
-        {
-            printf("An error occurred reading ROM code: %d", status);
-        }
-    }
-    else
-    {
-        // Search for a known ROM code (LSB first):
-        // For example: 0x1502162ca5b2ee28
-        OneWireBus_ROMCode known_device = {
-            .fields.family = { 0x28 },
-            .fields.serial_number = { 0xee, 0xb2, 0xa5, 0x2c, 0x16, 0x02 },
-            .fields.crc = { 0x15 },
-        };
-        char rom_code_s[OWB_ROM_CODE_STRING_LENGTH];
-        owb_string_from_rom_code(known_device, rom_code_s, sizeof(rom_code_s));
-        bool is_present = false;
-
-        owb_status search_status = owb_verify_rom(owb, known_device, &is_present);
-        if (search_status == OWB_STATUS_OK)
-        {
-            printf("Device %s is %s\n", rom_code_s, is_present ? "present" : "not present");
-        }
-        else
-        {
-            printf("An error occurred searching for known device: %d", search_status);
-        }
-    }
-
     // Create DS18B20 devices on the 1-Wire bus
     DS18B20_Info * devices[MAX_DEVICES] = {0};
     for (int i = 0; i < num_devices; ++i)
@@ -136,18 +158,6 @@ _Noreturn void app_main()
         ds18b20_set_resolution(ds18b20_info, DS18B20_RESOLUTION);
     }
 
-//    // Read temperatures from all sensors sequentially
-//    while (1)
-//    {
-//        printf("\nTemperature readings (degrees C):\n");
-//        for (int i = 0; i < num_devices; ++i)
-//        {
-//            float temp = ds18b20_get_temp(devices[i]);
-//            printf("  %d: %.3f\n", i, temp);
-//        }
-//        vTaskDelay(1000 / portTICK_PERIOD_MS);
-//    }
-
     // Check for parasitic-powered devices
     bool parasitic_power = false;
     ds18b20_check_for_parasite_power(owb, &parasitic_power);