Arduino C6 ULP example

Author: Jason2866

.github/workflows/examples.yml

@@ -26,6 +26,7 @@ jobs:
           - "examples/espidf-arduino-matter-light"
           - "examples/espidf-arduino-blink"
           - "examples/espidf-arduino-littlefs"
+          - "examples/espidf-arduino-C6-ULP-blink"
           - "examples/espidf-blink"
           - "examples/espidf-coap-server"
           - "examples/espidf-exceptions"
@@ -44,6 +45,8 @@ jobs:
             example: "examples/espidf-ulp-lp"
           - os: windows-latest
             example: "examples/espidf-ulp-riscv"
+          - os: windows-latest
+            example: "examples/espidf-arduino-C6-ULP-blink"
           - os: windows-latest
             example: "examples/espidf-arduino-matter-light"
     runs-on: ${{ matrix.os }}

examples/espidf-arduino-C6-ULP-blink/.gitignore

@@ -0,0 +1,5 @@
+.pio
+.vscode
+.dependencies.lock
+sdkconfig.esp32c6
+managed_components

examples/espidf-arduino-C6-ULP-blink/CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.16.0)
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(espidf-arduino-c6-ulp-blink)

examples/espidf-arduino-C6-ULP-blink/README.md

@@ -0,0 +1,9 @@
+# Arduino ULP Example for the ESP32-C6
+
+This example shows how to run a C program on the ESP32-C6 ULP core with Arduino (as an component of ESP-IDF) 
+
+## Two programs run parallel
+
+1. **Arduino on the High Power Core (HP Core):** The Arduino program blinks the onboard RGB
+2. **C Program on the Ultra-Low Power Core (ULP):** The ULP C program blinks an external LED connected to GPIO3
+

examples/espidf-arduino-C6-ULP-blink/include/README

@@ -0,0 +1,39 @@
+
+This directory is intended for project header files.
+
+A header file is a file containing C declarations and macro definitions
+to be shared between several project source files. You request the use of a
+header file in your project source file (C, C++, etc) located in `src` folder
+by including it, with the C preprocessing directive `#include'.
+
+```src/main.c
+
+#include "header.h"
+
+int main (void)
+{
+ ...
+}
+```
+
+Including a header file produces the same results as copying the header file
+into each source file that needs it. Such copying would be time-consuming
+and error-prone. With a header file, the related declarations appear
+in only one place. If they need to be changed, they can be changed in one
+place, and programs that include the header file will automatically use the
+new version when next recompiled. The header file eliminates the labor of
+finding and changing all the copies as well as the risk that a failure to
+find one copy will result in inconsistencies within a program.
+
+In C, the usual convention is to give header files names that end with `.h'.
+It is most portable to use only letters, digits, dashes, and underscores in
+header file names, and at most one dot.
+
+Read more about using header files in official GCC documentation:
+
+* Include Syntax
+* Include Operation
+* Once-Only Headers
+* Computed Includes
+
+https://gcc.gnu.org/onlinedocs/cpp/Header-Files.html

examples/espidf-arduino-C6-ULP-blink/lib/README

@@ -0,0 +1,46 @@
+
+This directory is intended for project specific (private) libraries.
+PlatformIO will compile them to static libraries and link into executable file.
+
+The source code of each library should be placed in a an own separate directory
+("lib/your_library_name/[here are source files]").
+
+For example, see a structure of the following two libraries `Foo` and `Bar`:
+
+|--lib
+|  |
+|  |--Bar
+|  |  |--docs
+|  |  |--examples
+|  |  |--src
+|  |     |- Bar.c
+|  |     |- Bar.h
+|  |  |- library.json (optional, custom build options, etc) https://docs.platformio.org/page/librarymanager/config.html
+|  |
+|  |--Foo
+|  |  |- Foo.c
+|  |  |- Foo.h
+|  |
+|  |- README --> THIS FILE
+|
+|- platformio.ini
+|--src
+   |- main.c
+
+and a contents of `src/main.c`:
+```
+#include <Foo.h>
+#include <Bar.h>
+
+int main (void)
+{
+  ...
+}
+
+```
+
+PlatformIO Library Dependency Finder will find automatically dependent
+libraries scanning project source files.
+
+More information about PlatformIO Library Dependency Finder
+- https://docs.platformio.org/page/librarymanager/ldf.html

examples/espidf-arduino-C6-ULP-blink/platformio.ini

@@ -0,0 +1,15 @@
+; PlatformIO Project Configuration File
+;
+; Build options: build flags, source filter, extra scripting
+; Upload options: custom port, speed, and extra flags
+; Library options: dependencies, extra library storages
+; 
+; Documentation: https://docs.platformio.org/page/projectconf.html
+
+[env:esp32c6]
+platform = espressif32
+framework = arduino, espidf
+board = esp32-c6-devkitc-1
+monitor_speed = 115200                                         
+lib_deps = 
+    Adafruit [email protected]

examples/espidf-arduino-C6-ULP-blink/sdkconfig.defaults

@@ -0,0 +1,19 @@
+# C6 devkit has 8 MB flash
+CONFIG_ESPTOOLPY_FLASHSIZE_8MB=y
+
+# Enable ULP
+CONFIG_ULP_COPROC_ENABLED=y
+CONFIG_ULP_COPROC_TYPE_LP_CORE=y
+CONFIG_ULP_COPROC_RESERVE_MEM=8192
+
+# Set log level
+CONFIG_BOOTLOADER_LOG_LEVEL_WARN=y
+CONFIG_BOOTLOADER_LOG_LEVEL=2
+CONFIG_LOG_DEFAULT_LEVEL_WARN=y
+CONFIG_LOG_DEFAULT_LEVEL=2
+
+# Arduino settings
+CONFIG_AUTOSTART_ARDUINO=y
+CONFIG_FREERTOS_HZ=1000
+CONFIG_MBEDTLS_PSK_MODES=y
+CONFIG_MBEDTLS_KEY_EXCHANGE_PSK=y

examples/espidf-arduino-C6-ULP-blink/src/CMakeLists.txt

@@ -0,0 +1,20 @@
+idf_component_register(SRCS "main.cpp")
+
+#
+# ULP support additions to component CMakeLists.txt.
+#
+# 1. The ULP app name must be "ulp_main"
+set(ulp_app_name ulp_main)
+#
+# 2. Specify all assembly source files.
+#    Paths are relative because ULP files are placed into a special directory "ulp"
+#    in the root of the project
+set(ulp_s_sources "../ulp/blink.c")
+#
+# 3. List all the component source files which include automatically
+#    generated ULP export file, ${ulp_app_name}.h:
+set(ulp_exp_dep_srcs "main.c")
+#
+# 4. Call function to build ULP binary and embed in project using the argument
+#    values above.
+ulp_embed_binary(${ulp_app_name} ${ulp_s_sources} ${ulp_exp_dep_srcs})

examples/espidf-arduino-C6-ULP-blink/src/main.cpp

@@ -0,0 +1,69 @@
+#include <Arduino.h>
+#include <Adafruit_NeoPixel.h>
+#include "ulp_lp_core.h"
+#include "esp_err.h"
+
+// Define the built-in RGB LED pin and number of LEDs
+#define LED_PIN 8
+#define NUM_LEDS 1
+
+Adafruit_NeoPixel rgbLed(NUM_LEDS, LED_PIN, NEO_GRB + NEO_KHZ800);
+
+// Define some colors
+struct RGB {
+    uint8_t r, g, b;
+};
+
+constexpr RGB COLOR_RED = {255, 0, 0};
+constexpr RGB COLOR_GREEN = {0, 255, 0};
+constexpr RGB COLOR_BLUE = {0, 0, 255};
+constexpr RGB COLOR_OFF = {0, 0, 0};
+
+extern const uint8_t bin_start[] asm("_binary_ulp_main_bin_start"); //refering to app name ulp_main defined in CMakelists.txt
+extern const uint8_t bin_end[]   asm("_binary_ulp_main_bin_end"); //refering to app name ulp_main defined in CMakelists.txt
+
+void start_ulp_program() {
+    // Change: Load the ULP binary into RTC memory
+    ESP_ERROR_CHECK(ulp_lp_core_load_binary(bin_start, (bin_end - bin_start)));
+
+    // Change: Configure the ULP LP core wake-up source and timer
+    ulp_lp_core_cfg_t cfg = {
+        .wakeup_source = ULP_LP_CORE_WAKEUP_SOURCE_LP_TIMER, // Wake up using LP timer
+        .lp_timer_sleep_duration_us = 1000000,              // 1-second sleep duration
+    };
+
+    // Change: Start the ULP LP core program
+    ESP_ERROR_CHECK(ulp_lp_core_run(&cfg));
+}
+
+void setColor(const RGB& color) {
+    rgbLed.setPixelColor(0, rgbLed.Color(color.r, color.g, color.b));
+    rgbLed.show();
+}
+
+void setup() {
+    Serial.begin(115200);
+    Serial.println("Starting ULP Program...");
+    start_ulp_program();
+    Serial.println("Starting RGB LED blinking...");
+    rgbLed.begin(); // Initialize the NeoPixel library
+    rgbLed.show();  // Turn off all LEDs initially
+}
+
+void loop() {
+    Serial.println("Setting color to RED");
+    setColor(COLOR_RED);
+    delay(1000);
+
+    Serial.println("Setting color to GREEN");
+    setColor(COLOR_GREEN);
+    delay(1000);
+
+    Serial.println("Setting color to BLUE");
+    setColor(COLOR_BLUE);
+    delay(1000);
+
+    Serial.println("Turning off LED");
+    setColor(COLOR_OFF);
+    delay(1000);
+}