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feat: add display UI with splash screen, dashboard, and RSSI sparkline

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Implement full SSD1306 OLED display support:
- Splash screen on boot (1.5s) with project name, version, board
- Dashboard showing radio state, config, counters, RSSI/SNR
- RSSI history sparkline (64-sample ring buffer, 2px-wide bars)
- DisplayOn/DisplayOff host commands routed via dedicated channel
- Pure render functions against generic DrawTarget (no hardware coupling)
- Display on/off control bypasses radio task entirely

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
swaitsandClaude Opus 4.6 committed 2026-03-29 20:42:54 -06:00
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vendor/static_cell/.cargo-checksum.json
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vendor/static_cell/.cargo_vcs_info.json
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vendor/static_cell/.github/bors.toml
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block_labels = ["needs-decision"]
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vendor/static_cell/.github/workflows/clippy.yml
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name: Clippy check
on:
push:
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pull_request:
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strategy:
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- name: Clippy check
run: cargo clippy
vendor/static_cell/.github/workflows/rustfmt.yml
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name: Code formatting check
on:
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pull_request:
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vendor/static_cell/.github/workflows/test.yml
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name: Test
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vendor/static_cell/CHANGELOG.md
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# Changelog
All notable changes to this project will be documented in this file.
The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
## 2.1.1 - 2025-06-22
- Soundness fix: ConstStaticCell should only be Send/Sync if T: Send. (#19, #20)
## 2.1.0 - 2024-04-26 - YANKED
- Added `ConstStaticCell` (#14)
## 2.0.0 - 2023-11-02
- Do not enable feature `critical-section` in `portable-atomic`. In targets that need
atomic polyfilling, you now need to explicitly enable either of `critical-section` or
`unsafe-assume-single-core` in `portable-atomic`.
## 1.3.0 - 2023-11-02
- Switch from `atomic-polyfill` to `portable-atomic`. Note: to be backwards compatible
this crate is enabling the `critical-section` feature in `portable-atomic`. If your
chip is single-core, you might want to upgrade to `static-cell` v2.0 so you can enable
the feature `unsafe-assume-single-core` instead, which is slightly more efficient.
## 1.2.0 - 2023-07-03
- Add panic-free `try_init()`, `try_init_with()`, `try_uninit()`.
## 1.1.0 - 2023-06-01
- Add `uninit()`.
- Add `make_static!` macro.
## 1.0.0 - 2022-08-22
- First release
vendor/static_cell/Cargo.lock
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# This file is automatically @generated by Cargo.
# It is not intended for manual editing.
version = 4
[[package]]
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version = "1.11.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "f84267b20a16ea918e43c6a88433c2d54fa145c92a811b5b047ccbe153674483"
[[package]]
name = "static_cell"
version = "2.1.1"
dependencies = [
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vendor/static_cell/Cargo.toml
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# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
#
# When uploading crates to the registry Cargo will automatically
# "normalize" Cargo.toml files for maximal compatibility
# with all versions of Cargo and also rewrite `path` dependencies
# to registry (e.g., crates.io) dependencies.
#
# If you are reading this file be aware that the original Cargo.toml
# will likely look very different (and much more reasonable).
# See Cargo.toml.orig for the original contents.
[package]
edition = "2021"
name = "static_cell"
version = "2.1.1"
build = false
autolib = false
autobins = false
autoexamples = false
autotests = false
autobenches = false
description = "Statically allocated, initialized at runtime cell."
readme = "README.md"
license = "MIT OR Apache-2.0"
repository = "https://github.com/embassy-rs/static-cell"
[package.metadata.docs.rs]
features = ["nightly"]
rustdoc-args = [
"--cfg",
"docsrs",
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[features]
nightly = []
[lib]
name = "static_cell"
path = "src/lib.rs"
[dependencies.portable-atomic]
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vendor/static_cell/LICENSE-APACHE
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Copyright (c) 2022 The critical-section authors
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vendor/static_cell/README.md
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# static-cell
[![crates.io](https://img.shields.io/crates/d/static_cell.svg)](https://crates.io/crates/static_cell)
[![crates.io](https://img.shields.io/crates/v/static_cell.svg)](https://crates.io/crates/static_cell)
[![Documentation](https://docs.rs/static_cell/badge.svg)](https://docs.rs/static_cell)
Statically allocated, initialized at runtime cell.
`StaticCell` provides a no-std-compatible, no-alloc way to reserve memory at compile time for
a value, but initialize it at runtime, and get a `'static` reference to it.
This is useful in the following scenarios:
- You need `&'static T`, but `T` can't be constructed in const context so you can't simply use a `static`.
- You need `&'static mut T`, not just `&'static T`.
## Example
```rust
use static_cell::StaticCell;
// Statically allocate memory for a `u32`.
static SOME_INT: StaticCell<u32> = StaticCell::new();
// Initialize it at runtime. This returns a `&'static mut`.
let x: &'static mut u32 = SOME_INT.init(42);
assert_eq!(*x, 42);
// Trying to call `.init()` again would panic, because the StaticCell is already initialized.
// SOME_INT.init(42);
```
## Alternatives
- If you can use `alloc`, you can use `Box::leak()`.
- If you're OK with `unsafe`, you can use `static mut THING: MaybeUninit<T>`.
- If you need just `&'static T` (instead of `&'static mut T`), there's [`OnceCell`](https://doc.rust-lang.org/stable/core/cell/struct.OnceCell.html) (not thread-safe though) or [`OnceLock`](https://doc.rust-lang.org/stable/std/sync/struct.OnceLock.html) (thread-safe, but requires `std`).
## Interoperability
This crate uses [`portable-atomic`](https://crates.io/crates/portable-atomic), so on targets without native
atomics you must import a crate that provides a [`critical-section`](https://github.com/rust-embedded/critical-section)
implementation. See the `critical-section` README for details.
## Minimum Supported Rust Version (MSRV)
This crate is guaranteed to compile on stable Rust 1.56 and up. It might compile with
older versions but that may change in any new patch release.
## License
This work is licensed under either of
- Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or
<http://www.apache.org/licenses/LICENSE-2.0>)
- MIT license ([LICENSE-MIT](LICENSE-MIT) or <http://opensource.org/licenses/MIT>)
at your option.
## Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.
vendor/static_cell/src/lib.rs
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#![cfg_attr(not(test), no_std)]
#![doc = include_str!("../README.md")]
#![cfg_attr(docsrs, feature(doc_cfg))]
#![cfg_attr(feature = "nightly", feature(type_alias_impl_trait))] // for tests
use core::cell::UnsafeCell;
use core::mem::MaybeUninit;
use portable_atomic::{AtomicBool, Ordering};
/// Statically allocated, initialized at runtime cell.
///
/// It has two states: "empty" and "full". It is created "empty", and obtaining a reference
/// to the contents permanently changes it to "full". This allows that reference to be valid
/// forever.
///
/// If your value can be initialized as a `const` value, consider using [`ConstStaticCell`]
/// instead if you only need to take the value at runtime.
///
/// See the [crate-level docs](crate) for usage.
pub struct StaticCell<T> {
used: AtomicBool,
val: UnsafeCell<MaybeUninit<T>>,
}
unsafe impl<T> Send for StaticCell<T> {}
unsafe impl<T> Sync for StaticCell<T> {}
impl<T> StaticCell<T> {
/// Create a new, empty `StaticCell`.
///
/// It can be initialized at runtime with [`StaticCell::init()`] or similar methods.
#[inline]
pub const fn new() -> Self {
Self {
used: AtomicBool::new(false),
val: UnsafeCell::new(MaybeUninit::uninit()),
}
}
/// Initialize the `StaticCell` with a value, returning a mutable reference to it.
///
/// Using this method, the compiler usually constructs `val` in the stack and then moves
/// it into the `StaticCell`. If `T` is big, this is likely to cause stack overflows.
/// Considering using [`StaticCell::init_with`] instead, which will construct it in-place inside the `StaticCell`.
///
/// # Panics
///
/// Panics if this `StaticCell` is already full.
#[inline]
#[allow(clippy::mut_from_ref)]
pub fn init(&'static self, val: T) -> &'static mut T {
self.uninit().write(val)
}
/// Initialize the `StaticCell` with the closure's return value, returning a mutable reference to it.
///
/// The advantage over [`StaticCell::init`] is that this method allows the closure to construct
/// the `T` value in-place directly inside the `StaticCell`, saving stack space.
///
/// # Panics
///
/// Panics if this `StaticCell` is already full.
#[inline]
#[allow(clippy::mut_from_ref)]
pub fn init_with(&'static self, val: impl FnOnce() -> T) -> &'static mut T {
self.uninit().write(val())
}
/// Return a mutable reference to the uninitialized memory owned by the `StaticCell`.
///
/// Using this method directly is not recommended, but it can be used to construct `T` in-place directly
/// in a guaranteed fashion.
///
/// # Panics
///
/// Panics if this `StaticCell` is already full.
#[inline]
#[allow(clippy::mut_from_ref)]
pub fn uninit(&'static self) -> &'static mut MaybeUninit<T> {
if let Some(val) = self.try_uninit() {
val
} else {
panic!("`StaticCell` is already full, it can't be initialized twice.");
}
}
/// Try initializing the `StaticCell` with a value, returning a mutable reference to it.
///
/// If this `StaticCell` is already full, it returns `None`.
///
/// Using this method, the compiler usually constructs `val` in the stack and then moves
/// it into the `StaticCell`. If `T` is big, this is likely to cause stack overflows.
/// Considering using [`StaticCell::try_init_with`] instead, which will construct it in-place inside the `StaticCell`.
///
/// Will only return a Some(&'static mut T) when the `StaticCell` was not yet initialized.
#[inline]
#[allow(clippy::mut_from_ref)]
pub fn try_init(&'static self, val: T) -> Option<&'static mut T> {
Some(self.try_uninit()?.write(val))
}
/// Try initializing the `StaticCell` with the closure's return value, returning a mutable reference to it.
///
/// If this `StaticCell` is already full, it returns `None`.
///
/// The advantage over [`StaticCell::init`] is that this method allows the closure to construct
/// the `T` value in-place directly inside the `StaticCell`, saving stack space.
///
#[inline]
#[allow(clippy::mut_from_ref)]
pub fn try_init_with(&'static self, val: impl FnOnce() -> T) -> Option<&'static mut T> {
Some(self.try_uninit()?.write(val()))
}
/// Try returning a mutable reference to the uninitialized memory owned by the `StaticCell`.
///
/// If this `StaticCell` is already full, it returns `None`.
///
/// Using this method directly is not recommended, but it can be used to construct `T` in-place directly
/// in a guaranteed fashion.
#[inline]
pub fn try_uninit(&'static self) -> Option<&'static mut MaybeUninit<T>> {
if self
.used
.compare_exchange(false, true, Ordering::Acquire, Ordering::Relaxed)
.is_ok()
{
// SAFETY: We just checked that the value is not yet taken and marked it as taken.
let val = unsafe { &mut *self.val.get() };
Some(val)
} else {
None
}
}
}
// ---
/// Statically allocated and initialized, taken at runtime cell.
///
/// It has two states: "untaken" and "taken". It is created "untaken", and obtaining a reference
/// to the contents permanently changes it to "taken". This allows that reference to be valid
/// forever.
///
/// If your value can be const defined, for example a large, zero filled buffer used for DMA
/// or other scratch memory usage, `ConstStaticCell` can be used to guarantee the initializer
/// will never take up stack memory.
///
/// If your values are all zero initialized, the resulting `ConstStaticCell` should be placed
/// in `.bss`, not taking flash space for initialization either.
///
/// See the [crate-level docs](crate) for usage.
pub struct ConstStaticCell<T> {
taken: AtomicBool,
val: UnsafeCell<T>,
}
// ConstStaticCell<T> essentially lets you construct a value of T, pass &ConstStaticCell<T> to
// another thread, and then in that thread obtain a &'static mut T, which is effectively sending
// the value between threads, therefore T must implement Send.
unsafe impl<T: Send> Send for ConstStaticCell<T> {}
unsafe impl<T: Send> Sync for ConstStaticCell<T> {}
impl<T> ConstStaticCell<T> {
/// Create a new, empty `ConstStaticCell`.
///
/// It can be taken at runtime with [`ConstStaticCell::take()`] or similar methods.
#[inline]
pub const fn new(value: T) -> Self {
Self {
taken: AtomicBool::new(false),
val: UnsafeCell::new(value),
}
}
/// Take the `ConstStaticCell`, returning a mutable reference to it.
///
/// # Panics
///
/// Panics if this `ConstStaticCell` was already taken.
#[inline]
#[allow(clippy::mut_from_ref)]
pub fn take(&'static self) -> &'static mut T {
if let Some(val) = self.try_take() {
val
} else {
panic!("`ConstStaticCell` is already taken, it can't be taken twice")
}
}
/// Try to take the `ConstStaticCell`, returning None if it was already taken
#[inline]
#[allow(clippy::mut_from_ref)]
pub fn try_take(&'static self) -> Option<&'static mut T> {
if self
.taken
.compare_exchange(false, true, Ordering::Acquire, Ordering::Relaxed)
.is_ok()
{
// SAFETY: We just checked that the value is not yet taken and marked it as taken.
let val = unsafe { &mut *self.val.get() };
Some(val)
} else {
None
}
}
}
/// Convert a `T` to a `&'static mut T`.
///
/// The macro declares a `static StaticCell` and then initializes it when run, returning the `&'static mut`.
/// Therefore, each instance can only be run once. Next runs will panic. The `static` can additionally be
/// decorated with attributes, such as `#[link_section]`, `#[used]`, et al.
///
/// This macro is nightly-only. It requires `#![feature(type_alias_impl_trait)]` in the crate using it.
///
/// # Examples
///
/// ```
/// # #![feature(type_alias_impl_trait)]
/// use static_cell::make_static;
///
/// # fn main() {
/// let x: &'static mut u32 = make_static!(42);
///
/// // This attribute instructs the linker to allocate it in the external RAM's BSS segment.
/// // This specific example is for ESP32S3 with PSRAM support.
/// let buf = make_static!([0u8; 4096], #[link_section = ".ext_ram.bss.buf"]);
///
/// // Multiple attributes can be supplied.
/// let s = make_static!(0usize, #[used] #[export_name = "exported_symbol_name"]);
/// # }
/// ```
#[cfg(feature = "nightly")]
#[cfg_attr(docsrs, doc(cfg(feature = "nightly")))]
#[macro_export]
macro_rules! make_static {
($val:expr) => ($crate::make_static!($val, ));
($val:expr, $(#[$m:meta])*) => {{
type T = impl ::core::marker::Sized;
$(#[$m])*
static STATIC_CELL: $crate::StaticCell<T> = $crate::StaticCell::new();
#[deny(unused_attributes)]
let (x,) = STATIC_CELL.uninit().write(($val,));
x
}};
}
#[cfg(test)]
mod tests {
use crate::StaticCell;
#[test]
fn test_static_cell() {
static CELL: StaticCell<u32> = StaticCell::new();
let val: &'static u32 = CELL.init(42u32);
assert_eq!(*val, 42);
}
#[cfg(feature = "nightly")]
#[test]
fn test_make_static() {
let val: &'static u32 = make_static!(42u32);
assert_eq!(*val, 42);
}
}
#[cfg(doctest)]
mod compile_fail_tests {
/// ```compile_fail
/// use std::rc::Rc;
///
/// use static_cell::ConstStaticCell;
///
/// fn main() {
/// let rc = Rc::new(0);
/// let sc = ConstStaticCell::new(rc.clone());
/// let t = std::thread::spawn(move || {
/// let sc = Box::leak(Box::new(sc));
/// let rc: &mut Rc<i32> = sc.take();
/// _ = rc.clone(); // data race!
/// });
/// _ = rc.clone();
/// _ = t.join();
/// }
/// ```
fn send_requires_send() {}
/// ```compile_fail
/// use std::rc::Rc;
///
/// use static_cell::ConstStaticCell;
///
/// fn main() {
/// let rc = Rc::new(0);
/// let sc = Box::leak(Box::new(ConstStaticCell::new(rc.clone())));
/// let t = std::thread::spawn(|| {
/// let rc: &mut Rc<i32> = sc.take();
/// _ = rc.clone(); // data race!
/// });
/// _ = rc.clone();
/// _ = t.join();
/// }
/// ```
fn sync_requires_send() {}
}