commit ce70442a2abaf2ae8c546fae846600038e09384e
Author: Lucas Schumacher <technolucas@protonmail.com>
Date:   Wed Nov 15 21:11:31 2023 -0500

    first commit

diff --git a/.cargo/config.toml b/.cargo/config.toml
new file mode 100644
index 0000000..c2924b9
--- /dev/null
+++ b/.cargo/config.toml
@@ -0,0 +1,17 @@
+[build]
+target = "xtensa-esp32-espidf"
+
+[target.xtensa-esp32-espidf]
+linker = "ldproxy"
+# runner = "espflash --monitor" # Select this runner for espflash v1.x.x
+runner = "espflash flash --monitor" # Select this runner for espflash v2.x.x
+rustflags = [ "--cfg",  "espidf_time64"] # Extending time_t for ESP IDF 5: https://github.com/esp-rs/rust/issues/110
+
+[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 = "v5.1.1"
+
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..73a638b
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+/.vscode
+/.embuild
+/target
+/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..9d0ae97
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,31 @@
+[package]
+name = "esp32-sound"
+version = "0.1.0"
+authors = ["Lucas Schumacher <technolucas@protonmail.com>"]
+edition = "2021"
+resolver = "2"
+rust-version = "1.71"
+
+[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 = ["std", "embassy", "esp-idf-svc/native"]
+
+pio = ["esp-idf-svc/pio"]
+std = ["alloc", "esp-idf-svc/binstart", "esp-idf-svc/std"]
+alloc = ["esp-idf-svc/alloc"]
+nightly = ["esp-idf-svc/nightly"]
+experimental = ["esp-idf-svc/experimental"]
+embassy = ["esp-idf-svc/embassy-sync", "esp-idf-svc/critical-section", "esp-idf-svc/embassy-time-driver"]
+
+[dependencies]
+log = { version = "0.4", default-features = false }
+esp-idf-svc = { version = "0.47.3", default-features = false }
+
+[build-dependencies]
+embuild = "0.31.3"
diff --git a/build.rs b/build.rs
new file mode 100644
index 0000000..112ec3f
--- /dev/null
+++ b/build.rs
@@ -0,0 +1,3 @@
+fn main() {
+    embuild::espidf::sysenv::output();
+}
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
new file mode 100644
index 0000000..a2f5ab5
--- /dev/null
+++ b/rust-toolchain.toml
@@ -0,0 +1,2 @@
+[toolchain]
+channel = "esp"
diff --git a/sdkconfig.defaults b/sdkconfig.defaults
new file mode 100644
index 0000000..9ea5d73
--- /dev/null
+++ b/sdkconfig.defaults
@@ -0,0 +1,10 @@
+# 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 granuality 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
diff --git a/src/main.rs b/src/main.rs
new file mode 100644
index 0000000..6d70a4d
--- /dev/null
+++ b/src/main.rs
@@ -0,0 +1,70 @@
+use std::{mem::transmute, time::Duration};
+
+use esp_idf_svc::hal::{
+    delay::TickType,
+    gpio::AnyIOPin,
+    i2s::{
+        config::{DataBitWidth, StdConfig},
+        I2sDriver, I2sTx,
+    },
+    peripherals::Peripherals,
+};
+
+const TBL_LEN: usize = 1024;
+const RATE: u32 = 48000;
+
+fn main() -> ! {
+    // It is necessary to call this function once. Otherwise some patches to the runtime
+    // implemented by esp-idf-sys might not link properly. See https://github.com/esp-rs/esp-idf-template/issues/71
+    esp_idf_svc::sys::link_patches();
+
+    // Bind the log crate to the ESP Logging facilities
+    esp_idf_svc::log::EspLogger::initialize_default();
+
+    log::info!("Hello, world!");
+    let peripherals = Peripherals::take().unwrap();
+
+    let mut wav_tbl: [i16; TBL_LEN] = [0; TBL_LEN];
+
+    log::info!("Generating wave table...");
+    for (i, sample) in wav_tbl.iter_mut().enumerate() {
+        *sample = ((2.0 * std::f32::consts::PI * (i as f32 / TBL_LEN as f32)).sin()
+            * std::i16::MAX as f32) as i16;
+    }
+    log::info!("Done generating wave table!");
+
+    //TODO! setup SGTL5000 via i2c
+    //
+    // start i2c
+    //
+
+    //i2s setup
+    let std_config = StdConfig::philips(RATE, DataBitWidth::Bits16);
+    let bclk = peripherals.pins.gpio1;
+    let _din = peripherals.pins.gpio4;
+    let dout = peripherals.pins.gpio6;
+    let mclk = AnyIOPin::none();
+    let ws = peripherals.pins.gpio2;
+    let mut i2s =
+        I2sDriver::<I2sTx>::new_std_tx(peripherals.i2s0, &std_config, bclk, dout, mclk, ws)
+            .unwrap();
+    i2s.tx_enable().unwrap();
+
+    let mut buffer: [i16; 1024] = [0; 1024]; // Should be even length
+    let mut phase: f32 = 0.0;
+    let phase_delta = (440.0 / RATE as f32) * TBL_LEN as f32;
+    let timeout = TickType::from(Duration::from_secs_f32(
+        2. * buffer.len() as f32 / RATE as f32,
+    ));
+    loop {
+        // Generate 440hz tone
+        for i in (0..buffer.len() - 1).step_by(2) {
+            buffer[i] = wav_tbl[phase as usize];
+            buffer[i + 1] = wav_tbl[phase as usize];
+            phase = (phase + phase_delta) % (TBL_LEN as f32);
+        }
+        let bytes: &[u8; 2048] = unsafe { transmute(&buffer) };
+        // Send samples to i2s device
+        i2s.write_all(bytes, timeout.0).unwrap();
+    }
+}