finished first interrupt example

Cargo.toml

@@ -10,6 +10,7 @@ members = [
   "mdbook/src/11-i2c",
   "mdbook/src/12-led-compass",
   "mdbook/src/13-punch-o-meter",
+  "mdbook/src/14-interrupts",
   "mdbook/src/14-snake-game",
   "mdbook/src/appendix/3-mag-calibration",
   "mdbook/src/serial-setup",

mdbook/src/14-interrupts/.cargo/config.toml

@@ -0,0 +1,8 @@
+[build]
+target = "thumbv7em-none-eabihf"
+
+[target.thumbv7em-none-eabihf]
+runner = "probe-rs run --chip nRF52833_xxAA"
+rustflags = [
+  "-C", "linker=rust-lld",
+]

mdbook/src/14-interrupts/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "interrupts"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+microbit-v2 = "0.15"
+cortex-m-rt = "0.7"
+rtt-target = "0.5"
+panic-rtt-target = "0.1"
+heapless = "0.8"
+tiny-led-matrix = "1.0"
+embedded-hal = "1.0"
+
+[dependencies.cortex-m]
+version = "0.7"
+features = ["critical-section-single-core"]

mdbook/src/14-interrupts/Embed.toml

@@ -0,0 +1,11 @@
+[default.general]
+chip = "nrf52833_xxAA"  # micro:bit V2
+
+[default.reset]
+halt_afterwards = false
+
+[default.rtt]
+enabled = true
+
+[default.gdb]
+enabled = false

mdbook/src/14-interrupts/examples/poke.rs

@@ -0,0 +1,40 @@
+#![no_main]
+#![no_std]
+
+use cortex_m::asm;
+use cortex_m_rt::entry;
+use panic_rtt_target as _;
+use rtt_target::{rprintln, rtt_init_print};
+
+use microbit::{
+    Board,
+    hal::{
+        gpiote,
+        pac::{self, interrupt},
+    },
+};
+
+#[interrupt]
+fn GPIOTE() {
+    rprintln!("ouch");
+    asm::bkpt();
+}
+
+#[entry]
+fn main() -> ! {
+    rtt_init_print!();
+    let board = Board::take().unwrap();
+    let button_a = board.buttons.button_a.into_floating_input();
+    let gpiote = gpiote::Gpiote::new(board.GPIOTE);
+    let channel = gpiote.channel0();
+            channel
+            .input_pin(&button_a.degrade())
+            .lo_to_hi()
+            .enable_interrupt();
+        channel.reset_events();
+    unsafe { pac::NVIC::unmask(pac::Interrupt::GPIOTE) };
+    pac::NVIC::unpend(pac::Interrupt::GPIOTE);
+    loop {
+        asm::wfe();
+    }
+}

mdbook/src/14-interrupts/examples/timer.rs

@@ -0,0 +1,30 @@
+#![no_main]
+#![no_std]
+
+use cortex_m::asm;
+use cortex_m_rt::entry;
+use panic_rtt_target as _;
+use rtt_target::{rprintln, rtt_init_print};
+
+use microbit::hal::{
+    gpio,
+    gpiote,
+    pac::{self, interrupt},
+    timer,
+};
+
+struct Blinker {
+    period: u32,
+    timer: timer::Timer<>
+
+static BLINKER: Option<Mutex<RefCell
+
+#[interrupt]
+fn TIMER0() {
+    rprintln!("tick");
+}
+
+#[entry]
+fn main() -> ! {
+
+}