esp-hal/examples/src/bin/wifi_embassy_ble.rs

//! Embassy BLE Example
//!
//! - starts Bluetooth advertising
//! - offers one service with three characteristics (one is read/write, one is write only, one is read/write/notify)
//! - pressing the boot-button on a dev-board will send a notification if it is subscribed

//% FEATURES: embassy embassy-generic-timers esp-wifi esp-wifi/async esp-wifi/ble
//% CHIPS: esp32 esp32s3 esp32c2 esp32c3 esp32c6 esp32h2

#![no_std]
#![no_main]

use core::cell::RefCell;

use bleps::{
    ad_structure::{
        create_advertising_data,
        AdStructure,
        BR_EDR_NOT_SUPPORTED,
        LE_GENERAL_DISCOVERABLE,
    },
    async_attribute_server::AttributeServer,
    asynch::Ble,
    attribute_server::NotificationData,
    gatt,
};
use embassy_executor::Spawner;
use esp_alloc as _;
use esp_backtrace as _;
use esp_hal::{
    gpio::{Input, Io, Pull},
    prelude::*,
    rng::Rng,
    time,
    timer::timg::TimerGroup,
};
use esp_println::println;
use esp_wifi::{ble::controller::BleConnector, init, EspWifiController};

// When you are okay with using a nightly compiler it's better to use https://docs.rs/static_cell/2.1.0/static_cell/macro.make_static.html
macro_rules! mk_static {
    ($t:ty,$val:expr) => {{
        static STATIC_CELL: static_cell::StaticCell<$t> = static_cell::StaticCell::new();
        #[deny(unused_attributes)]
        let x = STATIC_CELL.uninit().write(($val));
        x
    }};
}

#[esp_hal_embassy::main]
async fn main(_spawner: Spawner) -> ! {
    esp_println::logger::init_logger_from_env();
    let peripherals = esp_hal::init({
        let mut config = esp_hal::Config::default();
        config.cpu_clock = CpuClock::max();
        config
    });

    esp_alloc::heap_allocator!(72 * 1024);

    let timg0 = TimerGroup::new(peripherals.TIMG0);

    let init = &*mk_static!(
        EspWifiController<'static>,
        init(
            timg0.timer0,
            Rng::new(peripherals.RNG),
            peripherals.RADIO_CLK,
        )
        .unwrap()
    );

    let io = Io::new(peripherals.GPIO, peripherals.IO_MUX);
    cfg_if::cfg_if! {
        if #[cfg(any(feature = "esp32", feature = "esp32s2", feature = "esp32s3"))] {
            let button = Input::new(io.pins.gpio0, Pull::Down);
        } else {
            let button = Input::new(io.pins.gpio9, Pull::Down);
        }
    }

    cfg_if::cfg_if! {
        if #[cfg(feature = "esp32")] {
            let timg1 = TimerGroup::new(peripherals.TIMG1);
            esp_hal_embassy::init(timg1.timer0);
        } else {
            use esp_hal::timer::systimer::{SystemTimer, Target};
            let systimer = SystemTimer::new(peripherals.SYSTIMER).split::<Target>();
            esp_hal_embassy::init(systimer.alarm0);
        }
    }

    let mut bluetooth = peripherals.BT;

    let connector = BleConnector::new(&init, &mut bluetooth);

    let now = || time::now().duration_since_epoch().to_millis();
    let mut ble = Ble::new(connector, now);
    println!("Connector created");

    let pin_ref = RefCell::new(button);
    let pin_ref = &pin_ref;

    loop {
        println!("{:?}", ble.init().await);
        println!("{:?}", ble.cmd_set_le_advertising_parameters().await);
        println!(
            "{:?}",
            ble.cmd_set_le_advertising_data(
                create_advertising_data(&[
                    AdStructure::Flags(LE_GENERAL_DISCOVERABLE | BR_EDR_NOT_SUPPORTED),
                    AdStructure::ServiceUuids16(&[Uuid::Uuid16(0x1809)]),
                    AdStructure::CompleteLocalName(esp_hal::chip!()),
                ])
                .unwrap()
            )
            .await
        );
        println!("{:?}", ble.cmd_set_le_advertise_enable(true).await);

        println!("started advertising");

        let mut rf = |_offset: usize, data: &mut [u8]| {
            data[..20].copy_from_slice(&b"Hello Bare-Metal BLE"[..]);
            17
        };
        let mut wf = |offset: usize, data: &[u8]| {
            println!("RECEIVED: {} {:?}", offset, data);
        };

        let mut wf2 = |offset: usize, data: &[u8]| {
            println!("RECEIVED: {} {:?}", offset, data);
        };

        let mut rf3 = |_offset: usize, data: &mut [u8]| {
            data[..5].copy_from_slice(&b"Hola!"[..]);
            5
        };
        let mut wf3 = |offset: usize, data: &[u8]| {
            println!("RECEIVED: Offset {}, data {:?}", offset, data);
        };

        gatt!([service {
            uuid: "937312e0-2354-11eb-9f10-fbc30a62cf38",
            characteristics: [
                characteristic {
                    uuid: "937312e0-2354-11eb-9f10-fbc30a62cf38",
                    read: rf,
                    write: wf,
                },
                characteristic {
                    uuid: "957312e0-2354-11eb-9f10-fbc30a62cf38",
                    write: wf2,
                },
                characteristic {
                    name: "my_characteristic",
                    uuid: "987312e0-2354-11eb-9f10-fbc30a62cf38",
                    notify: true,
                    read: rf3,
                    write: wf3,
                },
            ],
        },]);

        let mut rng = bleps::no_rng::NoRng;
        let mut srv = AttributeServer::new(&mut ble, &mut gatt_attributes, &mut rng);

        let counter = RefCell::new(0u8);
        let counter = &counter;

        let mut notifier = || {
            // TODO how to check if notifications are enabled for the characteristic?
            // maybe pass something into the closure which just can query the characteristic
            // value probably passing in the attribute server won't work?

            async {
                pin_ref.borrow_mut().wait_for_rising_edge().await;
                let mut data = [0u8; 13];
                data.copy_from_slice(b"Notification0");
                {
                    let mut counter = counter.borrow_mut();
                    data[data.len() - 1] += *counter;
                    *counter = (*counter + 1) % 10;
                }
                NotificationData::new(my_characteristic_handle, &data)
            }
        };

        srv.run(&mut notifier).await.unwrap();
    }
}