[esp] Add Rust example with std.

esp/README.md

@@ -0,0 +1,8 @@
+# esp
+
+```bash
+shaunrd0/klips/esp/
+├── cpp     # Examples of ESP32 projects written in C++
+├── rust    # Examples of ESP32 projects written in Rust
+└── README.md
+```

esp/cpp/README.md

@@ -1,7 +1,7 @@
-# esp
+# esp/cpp
 
 ```bash
-shaunrd0/klips/esp/
+shaunrd0/klips/esp/cpp
 ├── 01_led-button               # Simple LED circuit controlled by an on board button.
 ├── 02_led-button-web           # LED controlled by a button or within a web browser.
 ├── 03_temp-humidity-web        # Temperature and humidity sensor within a web browser.

esp/rust/01_esp-idf-std/.cargo/config.toml

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+[build]
+target = "xtensa-esp32-espidf"
+
+[target.xtensa-esp32-espidf]
+linker = "ldproxy"
+runner = "espflash flash --monitor"
+rustflags = [ "--cfg",  "espidf_time64"]
+
+[unstable]
+build-std = ["std", "panic_abort"]
+
+[env]
+MCU="esp32"
+# Note: this variable is not used by the pio builder (`cargo build --features pio`)
+ESP_IDF_VERSION = "v5.2.3"
+

esp/rust/01_esp-idf-std/.gitignore

@@ -0,0 +1,5 @@
+/.vscode
+/.idea
+/.embuild
+/target
+/Cargo.lock

esp/rust/01_esp-idf-std/Cargo.toml

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+[package]
+name = "esp-idf-std"
+version = "0.1.0"
+authors = ["Shaun Reed <shaunrd0@gmail.com>"]
+edition = "2021"
+resolver = "2"
+rust-version = "1.77"
+
+[[bin]]
+name = "esp-idf-std"
+harness = false # do not use the built in cargo test harness -> resolve rust-analyzer errors
+
+[profile.release]
+opt-level = "s"
+
+[profile.dev]
+debug = true    # Symbols are nice and they don't increase the size on Flash
+opt-level = "z"
+
+[features]
+default = []
+
+experimental = ["esp-idf-svc/experimental"]
+
+[dependencies]
+log = "0.4"
+esp-idf-svc = "0.51"
+esp-idf-hal          = "0.45.2"
+anyhow = "1.0.98"
+
+# --- Optional Embassy Integration ---
+# esp-idf-svc = { version = "0.51", features = ["critical-section", "embassy-time-driver", "embassy-sync"] }
+
+# If you enable embassy-time-driver, you MUST also add one of:
+
+# a) Standalone Embassy libs ( embassy-time, embassy-sync etc) with a foreign async runtime:
+# embassy-time = { version = "0.4.0", features = ["generic-queue-8"] } # NOTE: any generic-queue variant will work
+
+# b) With embassy-executor:
+# embassy-executor = { version = "0.7", features = ["executor-thread", "arch-std"] }
+
+# NOTE: if you use embassy-time with embassy-executor you don't need the generic-queue-8 feature
+
+# --- Temporary workaround for embassy-executor < 0.8 ---
+# esp-idf-svc = { version = "0.51", features = ["embassy-time-driver", "embassy-sync"] }
+# critical-section = { version = "1.1", features = ["std"], default-features = false }
+
+[build-dependencies]
+embuild = "0.33"

esp/rust/01_esp-idf-std/README.md

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+# esp-idf-std
+
+This is an example of using ESP-IDF with std enabled in Rust
+When flashed to a device, the application just adjusts the intensity of the on-board LED for visual verification that flashing works correctly.
+
+Steps used to generate this project
+
+```bash
+cargo install cargo-generate
+cargo generate --git https://github.com/esp-rs/esp-idf-template.git --name esp-idf-rust-std -d mcu=esp32 -d std=true
+```
+
+Steps to build and flash this project
+
+```bash
+# Install espflash if you don't have it already
+cargo install espflash
+
+# Export esp-idf build environment
+. ~/export-esp.sh
+
+# Build and flash to the device
+cargo build
+cargo run
+
+# Check the serial monitor (optional)
+sudo usermod -aG dialout $USER
+newgrp dialout
+espflash monitor
+```
+
+For more detailed information on setting up a development environment, see [the esp/rust README](/esp/rust/README.md)

esp/rust/01_esp-idf-std/build.rs

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+fn main() {
+    embuild::espidf::sysenv::output();
+}

esp/rust/01_esp-idf-std/rust-toolchain.toml

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+[toolchain]
+channel = "esp"

esp/rust/01_esp-idf-std/sdkconfig.defaults

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+# Rust often needs a bit of an extra main task stack size compared to C (the default is 3K)
+CONFIG_ESP_MAIN_TASK_STACK_SIZE=8000
+
+# Use this to set FreeRTOS kernel tick frequency to 1000 Hz (100 Hz by default).
+# This allows to use 1 ms granularity for thread sleeps (10 ms by default).
+#CONFIG_FREERTOS_HZ=1000
+
+# Workaround for https://github.com/espressif/esp-idf/issues/7631
+#CONFIG_MBEDTLS_CERTIFICATE_BUNDLE=n
+#CONFIG_MBEDTLS_CERTIFICATE_BUNDLE_DEFAULT_FULL=n

esp/rust/01_esp-idf-std/src/main.rs

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+use esp_idf_hal::delay::FreeRtos;
+use esp_idf_hal::ledc::*;
+use esp_idf_hal::peripherals::Peripherals;
+use esp_idf_hal::prelude::*;
+
+fn main() -> anyhow::Result<()> {
+    esp_idf_hal::sys::link_patches();
+
+    println!("Configuring output channel");
+
+    let peripherals = Peripherals::take()?;
+    // Channel for on-board LED on ESP32
+    let mut channel = LedcDriver::new(
+        peripherals.ledc.channel0,
+        LedcTimerDriver::new(
+            peripherals.ledc.timer0,
+            &config::TimerConfig::new().frequency(25_u32.kHz().into()),
+        )?,
+        peripherals.pins.gpio2,
+    )?;
+
+    println!("Starting duty-cycle loop");
+    let max_duty = channel.get_max_duty();
+    // Cycle the channel duty every 2s to visually show that things are working when flashed.
+    for numerator in [0, 1, 2, 3, 4, 5].iter().cycle() {
+        println!("Duty {numerator}/5");
+        channel.set_duty(max_duty * numerator / 5)?;
+        FreeRtos::delay_ms(2000);
+    }
+
+    // We want this to run forever, so don't let the application terminate.
+    loop {
+        FreeRtos::delay_ms(1000);
+    }
+}

esp/rust/README.md

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+# esp/rust
+
+```bash
+shaunrd0/klips/esp/rust
+├── 01_es-idf-std   # Template project for using ESP-IDF with std enabled.
+└── README.md
+```
+
+## Development Setup
+
+Some notes I took while setting this up for the first time: [Knoats](https://knoats.com/books/esp32/page/rust)
+
+[Espressif Rust book](https://docs.espressif.com/projects/rust/book/introduction.html)