Add BLE example

Author: Henrik Alsér

examples/ble-beacon/Cargo.toml

@@ -0,0 +1,37 @@
+[package]
+name = "ble-beacon"
+version = "0.1.0"
+edition = "2018"
+
+[dependencies]
+embedded-hal = "0.2.4"
+cortex-m-rt = "0.6.12"
+panic-halt = "0.2.0"
+defmt-rtt = "0.2.0"
+defmt = "0.2.0"
+rubble = "0.0.4"
+rubble-nrf5x = { version = "0.0.4", default-features = false, features = ["51"] }
+
+[dependencies.microbit]
+path = "../../microbit"
+optional = true
+
+[dependencies.microbit-v2]
+path = "../../microbit-v2"
+optional = true
+
+[features]
+v1 = ["microbit"]
+v2 = ["microbit-v2"]
+
+default = [
+  "defmt-default",
+]
+
+# do NOT modify these features
+defmt-default = []
+defmt-trace = []
+defmt-debug = []
+defmt-info = []
+defmt-warn = []
+defmt-error = []

examples/ble-beacon/src/main.rs

@@ -0,0 +1,60 @@
+#![no_main]
+#![no_std]
+
+use panic_halt as _;
+
+use cortex_m_rt::entry;
+use embedded_hal::blocking::delay::DelayMs;
+use microbit::hal::{clocks::Clocks, timer::Timer};
+use rubble::beacon::Beacon;
+use rubble::link::{ad_structure::AdStructure, CompanyId, MIN_PDU_BUF};
+use rubble_nrf5x::radio::{BleRadio, PacketBuffer};
+use rubble_nrf5x::utils::get_device_address;
+
+#[entry]
+fn main() -> ! {
+    static mut BLE_TX_BUF: PacketBuffer = [0; MIN_PDU_BUF];
+    static mut BLE_RX_BUF: PacketBuffer = [0; MIN_PDU_BUF];
+    if let Some(p) = microbit::Peripherals::take() {
+        // On reset, the internal high frequency clock is already used, but we
+        // also need to switch to the external HF oscillator. This is needed
+        // for Bluetooth to work.
+        let _clocks = Clocks::new(p.CLOCK).enable_ext_hfosc();
+
+        // Determine device address
+        let device_address = get_device_address();
+
+        // Rubble currently requires an RX buffer even though the radio is only used as a TX-only beacon.
+        let mut radio = BleRadio::new(p.RADIO, &p.FICR, BLE_TX_BUF, BLE_RX_BUF);
+
+        let mut timer = Timer::new(p.TIMER0);
+
+        loop {
+            defmt::info!("Local name");
+            let beacon = Beacon::new(
+                device_address,
+                &[AdStructure::CompleteLocalName("Rusty microbit")],
+            )
+            .unwrap();
+            beacon.broadcast(&mut radio);
+            timer.delay_ms(1_000_u16);
+
+            let data = "Hello world";
+            defmt::info!("{}", data);
+            let beacon = Beacon::new(
+                device_address,
+                &[AdStructure::ManufacturerSpecificData {
+                    company_identifier: CompanyId::from_raw(0xffff),
+                    payload: data.as_bytes(),
+                }],
+            )
+            .unwrap();
+            beacon.broadcast(&mut radio);
+            timer.delay_ms(1_000_u16);
+        }
+    }
+
+    loop {
+        continue;
+    }
+}