apple · maartin0 · Mar 23, 2025
@@ -0,0 +1,46 @@
+name: Build Arduino ESP Examples
+
+on:
+  push:
+    branches: ["main"]
+  pull_request:
+    branches: ["main"]
+  schedule:
+    # Build on Mondays at 9am PST every week
+    - cron: '0 17 * * 1'
+
+jobs:
+  build-arduino-esp:
+    runs-on: ubuntu-24.04
+    container: espressif/idf:v5.4
+    strategy:
+      fail-fast: false
+      matrix:
+        example: [arduino-esp32-led-blink-sdk, arduino-esp32-wifi-scan-sdk]
+        swift: [swift-DEVELOPMENT-SNAPSHOT-2025-03-17-a]
+
+    steps:
+      - name: Checkout repo
+        uses: actions/checkout@v4
+
+      - name: Install apt dependencies
+        run: |
+          apt-get -qq update
+          apt-get -qq -y install pkg-config libstdc++6
+
+      - name: Install ${{ matrix.swift }}
+        run: |
+          wget -q https://download.swift.org/development/ubuntu2404/${{ matrix.swift }}/${{ matrix.swift }}-ubuntu24.04.tar.gz
+          tar xzf ${{ matrix.swift }}-ubuntu24.04.tar.gz
+          export PATH="`pwd`/${{ matrix.swift }}-ubuntu24.04/usr/bin/:$PATH"
+          echo "PATH=$PATH" >> $GITHUB_ENV
+          swiftc --version
+
+      - name: Build ${{ matrix.example }}
+        run: |
+          cd $IDF_PATH
+          . ./export.sh
+          cd -
+          cd ${{ matrix.example }}
+          idf.py set-target esp32c6
+          idf.py build
@@ -16,7 +16,7 @@ This repository is a set of demonstration projects of **Embedded Swift**. Embedd
 Each example in this repository contains build and deployment instructions, however there are a couple common steps needed for many of the examples included below:
 
 1. Install the latest downloadable 'main' [Development Snapshot](https://www.swift.org/install/macos/#development-snapshots) from swift.org to use Embedded Swift. Public releases of Swift do not yet support Embedded Swift.
-	
+
   You can follow the [tutorial here](https://apple.github.io/swift-matter-examples/tutorials/swiftmatterexamples/setup-macos/) for instructions on installing and using nighly Swift toolchains.
 
 2. Install [`uv`](https://github.com/astral-sh/uv) "an extremely fast Python package and project manager".
@@ -29,6 +29,8 @@ Each example in this repository contains build and deployment instructions, howe
 | ---- | -------- | --- | ----------- | ----- |
 | [esp32-led-blink-sdk](./esp32-led-blink-sdk) | ESP32-C6-Bug | ESP-IDF SDK | Blink an LED repeatedly with Swift & the ESP-IDF. | <img width="300" src="esp32-led-blink-sdk/assets/images/ledon.jpg"> |
 | [esp32-led-strip-sdk](./esp32-led-strip-sdk) | ESP32-C6-DevKitC-1 | ESP-IDF SDK | Control NeoPixel LEDs with Swift & the ESP-IDF. | <img width="300" src="https://github.com/apple/swift-embedded-examples/assets/1186214/15f8a3e0-953e-426d-ad2d-3902baf859be"> |
+| [arduino-esp32-led-blink-sdk](./arduino-esp32-led-blink-sdk) | ESP32-C6-Bug | ESP-IDF SDK | Blink an LED repeatedly with Swift, the ESP-IDF and the Arduino libraries. | |
+| [arduino-esp32-wifi-scan-sdk](./arduino-esp32-wifi-scan-sdk) | ESP32-C6-DevKitC-1 | ESP-IDF SDK | Blink an LED repeatedly with Swift, the ESP-IDF and the Arduino libraries. | |
 | [nrfx-blink-sdk](./nrfx-blink-sdk) | nRF52840-DK | Zephyr SDK | Blink an LED repeatedly with Swift & Zephyr. | <img width="300" src="https://github.com/apple/swift-embedded-examples/assets/1186214/ae3ff153-dd33-4460-8a08-4eac442bf7b0"> |
 | [nuttx-riscv-blink](./nuttx-riscv-blink) | QEMU | NuttX | Blink a virualized led in QEMU using the Apache NuttX RTOS | |
 | [pico-blink-sdk](./pico-blink-sdk) | Raspberry Pi Pico, Pico 2 | Pico SDK | Blink an LED repeatedly with Swift & the Pico SDK. | <img width="300" src="https://github.com/apple/swift-embedded-examples/assets/1186214/f2c45c18-f9a4-48b4-a941-1298ecc942cb"> |

@@ -0,0 +1,6 @@
+# The following lines of boilerplate have to be in your project's
+# CMakeLists in this exact order for cmake to work correctly
+cmake_minimum_required(VERSION 3.5)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(app-template)
@@ -0,0 +1,57 @@
+# arduino-esp32-led-blink-sdk
+
+This example demonstrates how to integrate with the ESP-IDF SDK via CMake and how to use the Arduino GPIO library to control an LED from Swift. This example is specifically made for the RISC-V MCUs from ESP32 (the Xtensa MCUs are not currently supported by Swift).
+
+## Requirements
+
+- Set up **version v5.4** (required for this `arduino-esp32` version) of the [ESP-IDF](https://docs.espressif.com/projects/esp-idf/en/v5.4/esp32/) development environment. Follow the steps in the [ESP32-C6 "Get Started" guide](https://docs.espressif.com/projects/esp-idf/en/v5.4/esp32c6/get-started/index.html).
+  - Make sure you specifically set up development for the RISC-V ESP32-C6, and not the Xtensa based products.
+  - If you have a different version of ESP-IDF installed, make sure to also delete `~/.espressif` before running `install.sh`
+
+```sh
+rm -rf ~/esp-idf ~/.espressif # Remove old installation files
+git clone --recurse-submodules https://github.com/espressif/esp-idf.git ~/esp-idf
+cd ~/esp-idf
+git checkout release/v5.4
+git submodule update --init --recursive
+./install.sh
+idf_tools.py install-python-env
+. ./export.sh
+```
+
+- Before trying to use Swift with the ESP-IDF SDK, make sure your environment works and can build the provided C/C++ sample projects, in particular:
+  - Try building and running the "get-started/blink" example from ESP-IDF written in C.
+
+## Building
+
+- Make sure you have a recent nightly Swift toolchain that has Embedded Swift support.
+- If needed, run export.sh to get access to the idf.py script from ESP-IDF.
+- Specify the nightly toolchain to be used via the `TOOLCHAINS` environment variable and the target board type by using `idf.py set-target`.
+```sh
+cd arduino-esp32-led-blink-sdk
+export TOOLCHAINS=...
+. <path-to-esp-idf>/export.sh
+idf.py set-target esp32c6
+idf.py build
+```
+
+## Running
+
+- Connect the Esp32-C6-Bug board (or any other board with integrated LED on GPIO pin 8) over a USB cable to your Mac. Alternatively you can just connect external LED to GPIO pin 8 on any other board.
+- Connect RX pin of USB-UART converter to TX0 pin of your board if you need serial output. You may also need to connect GND converter pin to the GND pin of the board.
+- Use `idf.py` to upload the firmware and to run it:
+
+```sh
+idf.py flash
+```
+
+- The LED should be blinking now.
+
+### Simulating in VS Code
+
+- Build the project, to generate binaries for simulation
+- Install [Wokwi for VS Code](https://docs.wokwi.com/vscode/getting-started/).
+- Open the `diagram.json` file.
+- Click the Play button to start simulation.
+- Click the Pause button to freeze simulation and display states of GPIOs.
+
@@ -0,0 +1,36 @@
+{
+  "version": 1,
+  "author": "",
+  "editor": "wokwi",
+  "parts": [
+    {
+      "type": "board-esp32-c6-devkitc-1",
+      "id": "esp",
+      "top": 0,
+      "left": 0,
+      "attrs": { "builder": "esp-idf" }
+    },
+    {
+      "type": "wokwi-resistor",
+      "id": "r1",
+      "top": 119.15,
+      "left": -76.8,
+      "attrs": { "value": "1000" }
+    },
+    {
+      "type": "wokwi-led",
+      "id": "led1",
+      "top": 25.2,
+      "left": -111.4,
+      "attrs": { "color": "red" }
+    }
+  ],
+  "connections": [
+    [ "esp:TX", "$serialMonitor:RX", "", [] ],
+    [ "esp:RX", "$serialMonitor:TX", "", [] ],
+    [ "r1:2", "esp:8", "red", [ "v0" ] ],
+    [ "r1:1", "led1:A", "red", [ "h0" ] ],
+    [ "led1:C", "esp:GND.1", "black", [ "v0" ] ]
+  ],
+  "dependencies": {}
+}
@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift open source project
+//
+// Copyright (c) 2025 Apple Inc. and the Swift project authors.
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+//
+//===----------------------------------------------------------------------===//
+
+// For some reason swiftc's clang++ defines `__UINT32_TYPE__` as `unsigned int` (g++'s x86 behaviour) not `long unsigned int` (g++'s riscv32 behaviour)
+#undef __UINT32_TYPE__
+#undef uint32_t
+#define __UINT32_TYPE__ long unsigned int
+#define uint32_t __UINT32_TYPE__
+#define _UINT32_T_DECLARED
+
+#include <stdio.h>
+#include <stdint.h>
+
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "driver/gpio.h"
+#include "sdkconfig.h"
+
+#include <Arduino.h>
@@ -0,0 +1,73 @@
+# Register the app as an IDF component
+idf_component_register(
+    SRCS /dev/null # We don't have any C++ sources
+    PRIV_INCLUDE_DIRS "."
+    REQUIRES arduino
+)
+
+idf_build_get_property(target IDF_TARGET)
+idf_build_get_property(arch IDF_TARGET_ARCH)
+
+if("${arch}" STREQUAL "xtensa")
+    message(FATAL_ERROR "Not supported target: ${target}")
+endif()
+
+# Extract the -march flag and remove any vendor-specific extensions (_x*)
+string(REGEX MATCH "-march=[^ ]+" march_flag "${CMAKE_C_FLAGS}")
+string(REGEX REPLACE "_x[^ ]*" "" march_flag "${march_flag}")
+
+# Extract the -mabi flag or set a default value if not present
+string(REGEX MATCH "-mabi=[^ ]+" mabi_flag "${CMAKE_C_FLAGS}")
+if("${mabi_flag}" STREQUAL "")
+    set(mabi_flag "-mabi=ilp32")
+endif()
+
+# Clear the default COMPILE_OPTIONS which include a lot of C/C++ specific compiler flags that the Swift compiler will not accept
+get_target_property(var ${COMPONENT_LIB} COMPILE_OPTIONS)
+set_target_properties(${COMPONENT_LIB} PROPERTIES COMPILE_OPTIONS "")
+
+# Compute -Xcc flags to set up the C and C++ header search paths for Swift (for bridging header).
+set(SWIFT_INCLUDES)
+foreach(dir ${CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES})
+    string(CONCAT SWIFT_INCLUDES ${SWIFT_INCLUDES} "-Xcc ")
+    string(CONCAT SWIFT_INCLUDES ${SWIFT_INCLUDES} "-I${dir} ")
+endforeach()
+foreach(dir ${CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES})
+    string(CONCAT SWIFT_INCLUDES ${SWIFT_INCLUDES} "-Xcc ")
+    string(CONCAT SWIFT_INCLUDES ${SWIFT_INCLUDES} "-I${dir} ")
+endforeach()
+
+# Swift compiler flags to build in Embedded Swift mode, optimize for size, choose the right ISA, ABI, etc.
+target_compile_options(${COMPONENT_LIB} PUBLIC "$<$<COMPILE_LANGUAGE:Swift>:SHELL:
+        -target riscv32-none-none-eabi
+        -Xfrontend -function-sections -enable-experimental-feature Embedded -wmo -parse-as-library -Osize -cxx-interoperability-mode=default
+        -Xcc ${march_flag} -Xcc ${mabi_flag} -Xcc -fno-pic -Xcc -fno-pie -Xcc -fno-exceptions
+
+        -pch-output-dir /tmp
+        -Xfrontend -enable-single-module-llvm-emission
+
+        ${SWIFT_INCLUDES}
+
+        -import-bridging-header ${CMAKE_CURRENT_LIST_DIR}/BridgingHeader.h
+    >")
+
+# Enable Swift support in CMake, force Whole Module builds (required by Embedded Swift), and use "CMAKE_Swift_COMPILER_WORKS" to
+# skip the trial compilations which don't (yet) correctly work when cross-compiling.
+set(CMAKE_Swift_COMPILER_WORKS YES)
+set(CMAKE_Swift_COMPILATION_MODE_DEFAULT wholemodule)
+set(CMAKE_Swift_COMPILATION_MODE wholemodule)
+enable_language(Swift)
+
+# List of Swift source files to build.
+target_sources(${COMPONENT_LIB}
+    PRIVATE
+    Main.swift
+    Led.swift
+)
+
+add_custom_command(
+    TARGET ${COMPONENT_LIB}
+    POST_BUILD
+    COMMAND ${CMAKE_OBJCOPY} --remove-section .swift_modhash
+            $<TARGET_FILE:${COMPONENT_LIB}> $<TARGET_FILE:${COMPONENT_LIB}>
+)
@@ -0,0 +1,8 @@
+# put here your custom config value
+menu "Example Configuration"
+config LED_BLINK_INTERVAL_MS
+    int "LED blinking interval / ms"
+    default 500
+    help
+	Interval in milliseconds between turning the LED on/off
+endmenu
@@ -0,0 +1,23 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift open source project
+//
+// Copyright (c) 2025 Apple Inc. and the Swift project authors.
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+//
+//===----------------------------------------------------------------------===//
+
+// A simple "overlay" to provide nicer APIs in Swift
+struct Led {
+  var ledPin: UInt8
+  init(gpioPin: gpio_num_t) {
+    ledPin = UInt8(gpioPin.rawValue)
+    pinMode(ledPin, UInt8(OUTPUT))
+  }
+
+  func setLed(value: Bool) {
+    digitalWrite(ledPin, value ? 1 : 0)
+  }
+}
@@ -0,0 +1,28 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Swift open source project
+//
+// Copyright (c) 2025 Apple Inc. and the Swift project authors.
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+//
+//===----------------------------------------------------------------------===//
+
+// The code will blink an LED on GPIO8. To change the pin, modify Led(gpioPin: GPIO_NUM_8)
+
+var ledValue: Bool = false
+var led: Led?
+
+@_cdecl("_Z5setupv")
+func setup() {
+  print("Hello from Swift on ESP32-C6!")
+  led = Led(gpioPin: GPIO_NUM_8)
+}
+
+@_cdecl("_Z4loopv")
+func loop() {
+  led?.setLed(value: ledValue)
+  ledValue.toggle()  // Toggle the boolean value
+  delay(UInt(CONFIG_LED_BLINK_INTERVAL_MS))
+}
@@ -0,0 +1,8 @@
+#
+# Main component makefile.
+#
+# This Makefile can be left empty. By default, it will take the sources in the 
+# src/ directory, compile them and link them into lib(subdirectory_name).a 
+# in the build directory. This behaviour is entirely configurable,
+# please read the ESP-IDF documents if you need to do this.
+#
@@ -0,0 +1,19 @@
+## IDF Component Manager Manifest File
+dependencies:
+  # # Put list of dependencies here
+  # # For components maintained by Espressif:
+  # component: "~1.0.0"
+  # # For 3rd party components:
+  # username/component: ">=1.0.0,<2.0.0"
+  # username2/component2:
+  #   version: "~1.0.0"
+  #   # For transient dependencies `public` flag can be set.
+  #   # `public` flag doesn't have an effect dependencies of the `main` component.
+  #   # All dependencies of `main` are public by default.
+  #   public: true
+
+  ## Required IDF version
+  idf: ">=5.3,<5.5"
+  arduino:  # Can't be defined as the espressif/arduino-esp32 shorthand since the library name must be 'arduino' for libraries that depend on it
+    git: https://github.com/espressif/arduino-esp32.git
+    version: 3.2.0
@@ -0,0 +1,4 @@
+CONFIG_FREERTOS_HZ=1000
+CONFIG_MBEDTLS_PSK_MODES=y
+CONFIG_MBEDTLS_KEY_EXCHANGE_PSK=y
+CONFIG_AUTOSTART_ARDUINO=y
@@ -0,0 +1,8 @@
+# Wokwi Configuration File
+# Reference: https://docs.wokwi.com/vscode/project-config
+[wokwi]
+version = 1
+firmware = 'build/flasher_args.json'
+elf = 'build/main.elf'
+# gdbServerPort=3333
+
@@ -0,0 +1,6 @@
+# The following lines of boilerplate have to be in your project's
+# CMakeLists in this exact order for cmake to work correctly
+cmake_minimum_required(VERSION 3.5)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(app-template)