feat(ds18b20): Add one_wire UART backend

Author: Narukara

components/.build-test-rules.yml

@@ -30,9 +30,13 @@ components/esp_lvgl_port/test_apps/simd:
 components/ds18b20:
   depends_filepatterns:
     - "components/ds18b20/**"
+
+components/ds18b20/examples/ds18b20_read:
   disable:
-    - if: SOC_RMT_SUPPORTED != 1
-      reason: Onewire component depends on RMT peripheral
+    - if: CONFIG_NAME == "rmt" and SOC_RMT_SUPPORTED != 1
+      reason: RMT backend variant requires SOC RMT support
+    - if: CONFIG_NAME == "uart" and SOC_UART_SUPPORTED != 1
+      reason: UART backend variant requires SOC UART support
 
 components/sensors/icm42670:
   depends_filepatterns:

components/ds18b20/CHANGELOG.md

@@ -1,3 +1,8 @@
+## 0.3.1
+
+- Bump dependency `onewire_bus` to `^1.1.0` to align with new backend capabilities (including UART backend support).
+- Update `ds18b20_read` example to support backend selection in menuconfig (RMT/UART).
+
 ## 0.3.0
 
 - Add detection for uninitialized power-on state (85.0C) and return `ESP_ERR_INVALID_STATE` when this value is read.

components/ds18b20/examples/ds18b20_read/README.md

@@ -4,16 +4,25 @@ This example shows how to use the 1-Wire temperature sensor DS18B20.
 
 ### Hardware Required
 
-* An ESP development board with RMT peripheral (e.g ESP32, ESP32-C3, ESP32-S3, etc)
-* An DS18B20 sensor connected to GPIO 18. To use a different pin, modify `EXAMPLE_ONEWIRE_BUS_GPIO` in [source file](main/ds18b20_example_main.c)
+* An ESP development board that supports the selected 1-Wire backend (`RMT` or `UART`)
+* A DS18B20 sensor connected to the configured 1-Wire GPIO (default: GPIO0)
 * An USB cable for power supply and programming
 
+### Configuration
+
+Run `idf.py menuconfig`, then open:
+
+* `Example Configuration` -> `1-Wire backend` to choose `RMT` or `UART`
+* `Example Configuration` -> `1-Wire bus GPIO number` to select bus pin
+* `Example Configuration` -> `Enable internal pull-up resistor on bus GPIO` as needed
+* `Example Configuration` -> `UART port number (for UART backend)` when UART backend is selected
+
 ### Example Output
 
 ```text
 ...
 I (297) main_task: Calling app_main()
-I (297) example: 1-Wire bus installed on GPIO18
+I (297) example: 1-Wire bus installed on GPIO0 by RMT backend
 I (297) example: Device iterator created, start searching...
 I (407) example: Found a DS18B20[0], address: 070822502019FC28
 I (517) example: Found a DS18B20[1], address: FC0921C076034628

components/ds18b20/examples/ds18b20_read/main/Kconfig.projbuild

@@ -0,0 +1,45 @@
+menu "Example Configuration"
+
+    config EXAMPLE_ONEWIRE_BUS_GPIO
+        int "1-Wire bus GPIO number"
+        range 0 48
+        default 0
+        help
+            GPIO used by the 1-Wire bus.
+
+    config EXAMPLE_ONEWIRE_MAX_DS18B20
+        int "Maximum number of DS18B20 devices to enumerate"
+        range 1 32
+        default 2
+        help
+            Stop searching after this many DS18B20 devices are found.
+
+    config EXAMPLE_ONEWIRE_ENABLE_INTERNAL_PULLUP
+        bool "Enable internal pull-up resistor on bus GPIO"
+        default y
+        help
+            Enable this when there is no external pull-up resistor on the
+            1-Wire data line.
+
+    choice EXAMPLE_ONEWIRE_BACKEND
+        prompt "1-Wire backend"
+        default EXAMPLE_ONEWIRE_BACKEND_RMT
+        help
+            Select which backend is used by onewire_bus.
+
+        config EXAMPLE_ONEWIRE_BACKEND_RMT
+            bool "RMT backend"
+
+        config EXAMPLE_ONEWIRE_BACKEND_UART
+            bool "UART backend"
+    endchoice
+
+    config EXAMPLE_ONEWIRE_UART_PORT_NUM
+        int "UART port number (for UART backend)"
+        range 0 2
+        default 1
+        depends on EXAMPLE_ONEWIRE_BACKEND_UART
+        help
+            UART port index passed to onewire_new_bus_uart().
+
+endmenu

components/ds18b20/examples/ds18b20_read/main/ds18b20_example_main.c

@@ -1,18 +1,29 @@
 /*
- * SPDX-FileCopyrightText: 2022-2025 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2026 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
 
 #include <stdio.h>
 #include "esp_log.h"
+#include "sdkconfig.h"
 #include "freertos/FreeRTOS.h"
 #include "freertos/task.h"
 #include "onewire_bus.h"
 #include "ds18b20.h"
 
-#define EXAMPLE_ONEWIRE_BUS_GPIO    18
-#define EXAMPLE_ONEWIRE_MAX_DS18B20 2
+#if CONFIG_EXAMPLE_ONEWIRE_ENABLE_INTERNAL_PULLUP
+#define EXAMPLE_ONEWIRE_ENABLE_INTERNAL_PULLUP 1
+#else
+#define EXAMPLE_ONEWIRE_ENABLE_INTERNAL_PULLUP 0
+#endif
+
+#if CONFIG_EXAMPLE_ONEWIRE_BACKEND_UART
+#define EXAMPLE_ONEWIRE_UART_PORT_NUM CONFIG_EXAMPLE_ONEWIRE_UART_PORT_NUM
+#endif
+
+#define EXAMPLE_ONEWIRE_BUS_GPIO    CONFIG_EXAMPLE_ONEWIRE_BUS_GPIO
+#define EXAMPLE_ONEWIRE_MAX_DS18B20 CONFIG_EXAMPLE_ONEWIRE_MAX_DS18B20
 
 static const char *TAG = "example";
 
@@ -23,14 +34,25 @@ void app_main(void)
     onewire_bus_config_t bus_config = {
         .bus_gpio_num = EXAMPLE_ONEWIRE_BUS_GPIO,
         .flags = {
-            .en_pull_up = true, // enable the internal pull-up resistor in case the external device didn't have one
+            .en_pull_up = EXAMPLE_ONEWIRE_ENABLE_INTERNAL_PULLUP,
         }
     };
+#if CONFIG_EXAMPLE_ONEWIRE_BACKEND_RMT
     onewire_bus_rmt_config_t rmt_config = {
         .max_rx_bytes = 10, // 1byte ROM command + 8byte ROM number + 1byte device command
     };
     ESP_ERROR_CHECK(onewire_new_bus_rmt(&bus_config, &rmt_config, &bus));
-    ESP_LOGI(TAG, "1-Wire bus installed on GPIO%d", EXAMPLE_ONEWIRE_BUS_GPIO);
+    ESP_LOGI(TAG, "1-Wire bus installed on GPIO%d by RMT backend", EXAMPLE_ONEWIRE_BUS_GPIO);
+#elif CONFIG_EXAMPLE_ONEWIRE_BACKEND_UART
+    onewire_bus_uart_config_t uart_config = {
+        .uart_port_num = EXAMPLE_ONEWIRE_UART_PORT_NUM,
+    };
+    ESP_ERROR_CHECK(onewire_new_bus_uart(&bus_config, &uart_config, &bus));
+    ESP_LOGI(TAG, "1-Wire bus installed on GPIO%d by UART backend (UART%d)",
+             EXAMPLE_ONEWIRE_BUS_GPIO, EXAMPLE_ONEWIRE_UART_PORT_NUM);
+#else
+#error "No 1-Wire backend selected in menuconfig"
+#endif
 
     int ds18b20_device_num = 0;
     ds18b20_device_handle_t ds18b20s[EXAMPLE_ONEWIRE_MAX_DS18B20];

components/ds18b20/examples/ds18b20_read/sdkconfig.bsp.rmt

@@ -0,0 +1 @@
+CONFIG_EXAMPLE_ONEWIRE_BACKEND_RMT=y

components/ds18b20/examples/ds18b20_read/sdkconfig.bsp.uart

@@ -0,0 +1,2 @@
+CONFIG_EXAMPLE_ONEWIRE_BACKEND_UART=y
+CONFIG_EXAMPLE_ONEWIRE_UART_PORT_NUM=1

components/ds18b20/idf_component.yml

@@ -1,5 +1,5 @@
-version: "0.3.0"
+version: "0.3.1"
 description: DS18B20 device driver
 url: https://github.com/espressif/esp-bsp/tree/master/components/ds18b20
 dependencies:
-  onewire_bus: "^1.0.0"
+  onewire_bus: "^1.1.0"