turn into a Cargo crate

examples/hello.rs

@@ -0,0 +1,24 @@
+//! Prints "Hello, world!" on the OpenOCD console using semihosting
+
+#![feature(used)]
+#![no_std]
+
+#[macro_use]
+extern crate cortex_m;
+extern crate cortex_m_rt;
+
+use cortex_m::asm;
+
+fn main() {
+    hprintln!("Hello, world!");
+}
+
+// As we are not using interrupts, we just register a dummy catch all handler
+#[allow(dead_code)]
+#[used]
+#[link_section = ".rodata.interrupts"]
+static INTERRUPTS: [extern "C" fn(); 240] = [default_handler; 240];
+
+extern "C" fn default_handler() {
+    asm::bkpt();
+}