diff --git a/wii-ext/src/nunchuk.rs b/wii-ext/src/nunchuk.rs
index 93335bc..7db771e 100644
--- a/wii-ext/src/nunchuk.rs
+++ b/wii-ext/src/nunchuk.rs
@@ -9,12 +9,7 @@
 
 use crate::core::nunchuk::{CalibrationData, NunchukReading, NunchukReadingCalibrated};
 use crate::interface::Interface;
-use crate::ControllerIdReport;
 use crate::ControllerType;
-use crate::ExtReport;
-use crate::EXT_I2C_ADDR;
-use crate::INTERMESSAGE_DELAY_MICROSEC_U32 as INTERMESSAGE_DELAY_MICROSEC;
-use embedded_hal::delay::DelayNs;
 use embedded_hal::i2c::{I2c, SevenBitAddress};
 
 #[derive(Debug)]
@@ -74,8 +69,7 @@ where
     }
 
     pub fn identify_controller(&mut self) -> Result<Option<ControllerType>, Error<ERR>> {
-        let i2c_id = self.interface.read_id()?;
-        Ok(crate::common::identify_controller(i2c_id))
+        self.interface.identify_controller()
     }
 
     /// Read the button/axis data from the nunchuk
@@ -103,6 +97,7 @@ where
 mod tests {
     use super::*;
     use crate::test_data;
+    use crate::EXT_I2C_ADDR;
     use embedded_hal_mock::eh1::{
         delay::NoopDelay,
         i2c::{self, Transaction},
diff --git a/wii-ext/tests/nunchuk.rs b/wii-ext/tests/nunchuk.rs
new file mode 100644
index 0000000..186d457
--- /dev/null
+++ b/wii-ext/tests/nunchuk.rs
@@ -0,0 +1,251 @@
+use embedded_hal_mock::eh1::{
+    delay::NoopDelay,
+    i2c::{self, Transaction},
+};
+use wii_ext::{nunchuk::Nunchuk, test_data, EXT_I2C_ADDR};
+/// There's a certain amount of slop around the center position.
+/// Allow up to this range without it being an error
+const ZERO_SLOP: i8 = 5;
+/// The max value at full deflection is ~100, but allow a bit less than that
+const AXIS_MAX: i8 = 90;
+
+// TODO: work out how to test analogue values from joystick and gyro
+
+#[test]
+fn nunchuck_idle() {
+    let expectations = vec![
+        // Reset controller
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        // Init
+        Transaction::write(EXT_I2C_ADDR as u8, vec![240, 85]),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![251, 0]),
+        // Calibration read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        // Read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+    ];
+
+    let mut mock = i2c::Mock::new(&expectations);
+    let delay = NoopDelay::new();
+    let mut nc = Nunchuk::new(mock.clone(), delay).unwrap();
+    let report = nc.read_blocking().unwrap();
+    assert!(!report.button_c);
+    assert!(!report.button_z);
+    mock.done();
+}
+
+#[test]
+fn nunchuck_idle_calibrated() {
+    let expectations = vec![
+        // Reset controller
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        // Init
+        Transaction::write(EXT_I2C_ADDR as u8, vec![240, 85]),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![251, 0]),
+        // Calibration read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        // Read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+    ];
+    let mut mock = i2c::Mock::new(&expectations);
+    let delay = NoopDelay::new();
+    let mut nc = Nunchuk::new(mock.clone(), delay).unwrap();
+    let report = nc.read_blocking().unwrap();
+    assert!(!report.button_c);
+    assert!(!report.button_z);
+    assert_eq!(report.joystick_x, 0);
+    assert_eq!(report.joystick_y, 0);
+    mock.done();
+}
+
+#[test]
+fn nunchuck_left_calibrated() {
+    let expectations = vec![
+        // Reset controller
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        // Init
+        Transaction::write(EXT_I2C_ADDR as u8, vec![240, 85]),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![251, 0]),
+        // Calibration read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        // Read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_JOY_L.to_vec()),
+    ];
+    let mut mock = i2c::Mock::new(&expectations);
+    let delay = NoopDelay::new();
+    let mut nc = Nunchuk::new(mock.clone(), delay).unwrap();
+    let report = nc.read_blocking().unwrap();
+    assert!(!report.button_c);
+    assert!(!report.button_z);
+    assert!(report.joystick_x < -AXIS_MAX, "x = {}", report.joystick_x);
+    assert!(report.joystick_y > -ZERO_SLOP, "y = {}", report.joystick_y);
+    assert!(report.joystick_y < ZERO_SLOP, "y = {}", report.joystick_y);
+    mock.done();
+}
+
+#[test]
+fn nunchuck_right_calibrated() {
+    let expectations = vec![
+        // Reset controller
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        // Init
+        Transaction::write(EXT_I2C_ADDR as u8, vec![240, 85]),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![251, 0]),
+        // Calibration read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        // Read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_JOY_R.to_vec()),
+    ];
+    let mut mock = i2c::Mock::new(&expectations);
+    let delay = NoopDelay::new();
+    let mut nc = Nunchuk::new(mock.clone(), delay).unwrap();
+    let report = nc.read_blocking().unwrap();
+    assert!(!report.button_c);
+    assert!(!report.button_z);
+    assert!(report.joystick_x > AXIS_MAX, "x = {}", report.joystick_x);
+    assert!(report.joystick_y > -ZERO_SLOP, "y = {}", report.joystick_y);
+    assert!(report.joystick_y < ZERO_SLOP, "y = {}", report.joystick_y);
+    mock.done();
+}
+
+#[test]
+fn nunchuck_up_calibrated() {
+    let expectations = vec![
+        // Reset controller
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        // Init
+        Transaction::write(EXT_I2C_ADDR as u8, vec![240, 85]),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![251, 0]),
+        // Calibration read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        // Read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_JOY_U.to_vec()),
+    ];
+    let mut mock = i2c::Mock::new(&expectations);
+    let delay = NoopDelay::new();
+    let mut nc = Nunchuk::new(mock.clone(), delay).unwrap();
+    let report = nc.read_blocking().unwrap();
+    assert!(!report.button_c);
+    assert!(!report.button_z);
+    assert!(report.joystick_y > AXIS_MAX, "y = {}", report.joystick_y);
+    assert!(report.joystick_x > -ZERO_SLOP, "x = {}", report.joystick_x);
+    assert!(report.joystick_x < ZERO_SLOP, "x = {}", report.joystick_x);
+    mock.done();
+}
+
+#[test]
+fn nunchuck_down_calibrated() {
+    let expectations = vec![
+        // Reset controller
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        // Init
+        Transaction::write(EXT_I2C_ADDR as u8, vec![240, 85]),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![251, 0]),
+        // Calibration read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        // Read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_JOY_D.to_vec()),
+    ];
+    let mut mock = i2c::Mock::new(&expectations);
+    let delay = NoopDelay::new();
+    let mut nc = Nunchuk::new(mock.clone(), delay).unwrap();
+    let report = nc.read_blocking().unwrap();
+    assert!(!report.button_c);
+    assert!(!report.button_z);
+    assert!(report.joystick_y < -AXIS_MAX, "y = {}", report.joystick_y);
+    assert!(report.joystick_x > -ZERO_SLOP, "x = {}", report.joystick_x);
+    assert!(report.joystick_x < ZERO_SLOP, "x = {}", report.joystick_x);
+    mock.done();
+}
+
+#[test]
+fn nunchuck_idle_repeat() {
+    let expectations = vec![
+        // Reset controller
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        // Init
+        Transaction::write(EXT_I2C_ADDR as u8, vec![240, 85]),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![251, 0]),
+        // Calibration read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        // Read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+    ];
+    let mut mock = i2c::Mock::new(&expectations);
+    let delay = NoopDelay::new();
+    let mut nc = Nunchuk::new(mock.clone(), delay).unwrap();
+
+    let report = nc.read_report_blocking().unwrap();
+    assert!(!report.button_c);
+    assert!(!report.button_z);
+    let report = nc.read_report_blocking().unwrap();
+    assert!(!report.button_c);
+    assert!(!report.button_z);
+    mock.done();
+}
+
+#[test]
+fn nunchuck_btn_c() {
+    let expectations = vec![
+        // Reset controller
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        // Init
+        Transaction::write(EXT_I2C_ADDR as u8, vec![240, 85]),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![251, 0]),
+        // Calibration read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        // Read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_BTN_C.to_vec()),
+    ];
+    let mut mock = i2c::Mock::new(&expectations);
+    let delay = NoopDelay::new();
+    let mut nc = Nunchuk::new(mock.clone(), delay).unwrap();
+
+    let report = nc.read_report_blocking().unwrap();
+    assert!(report.button_c);
+    assert!(!report.button_z);
+    mock.done();
+}
+
+#[test]
+fn nunchuck_btn_z() {
+    let expectations = vec![
+        // Reset controller
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        // Init
+        Transaction::write(EXT_I2C_ADDR as u8, vec![240, 85]),
+        Transaction::write(EXT_I2C_ADDR as u8, vec![251, 0]),
+        // Calibration read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_IDLE.to_vec()),
+        // Read
+        Transaction::write(EXT_I2C_ADDR as u8, vec![0]),
+        Transaction::read(EXT_I2C_ADDR as u8, test_data::NUNCHUCK_BTN_Z.to_vec()),
+    ];
+    let mut mock = i2c::Mock::new(&expectations);
+    let delay = NoopDelay::new();
+    let mut nc = Nunchuk::new(mock.clone(), delay).unwrap();
+
+    let report = nc.read_report_blocking().unwrap();
+    assert!(!report.button_c);
+    assert!(report.button_z);
+    mock.done();
+}