blocking SPI API

src/blocking/mod.rs

@@ -0,0 +1,3 @@
+//! Blocking API
+
+pub mod spi;

src/blocking/spi.rs

@@ -0,0 +1,16 @@
+//! Blocking SPI API
+
+use Spi;
+
+/// Transfers bytes to the slave, returns the bytes received from the slave
+pub fn transfer<'a, S>(spi: &mut S, bytes: &'a mut [u8]) -> Result<&'a [u8], S::Error>
+where
+    S: Spi<u8>,
+{
+    for byte in bytes.iter_mut() {
+        block!(spi.send(*byte))?;
+        *byte = block!(spi.read())?;
+    }
+
+    Ok(bytes)
+}

src/lib.rs

@@ -609,8 +609,10 @@
 #![feature(never_type)]
 #![no_std]
 
+#[macro_use]
 extern crate nb;
 
+pub mod blocking;
 pub mod prelude;
 pub mod serial;