diff --git a/Cargo.toml b/Cargo.toml
index 46c718a..d9cf6b1 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,46 +13,30 @@ license = "BSD-2-Clause"
 volatile-register = "0.2"
 aligned = "0.3"
 embedded-hal = "0.2"
-smoltcp = { version = "0.7.0", default-features = false, features = [ "socket-raw", "proto-ipv4", "proto-ipv6" ], optional = true }
-# Dependencies for NAL
-embedded-time = { version = "0.10.1", optional = true }
-embedded-nal = { version = "0.1.0", optional = true }
-heapless = { version = "0.5.6", optional = true }
+smoltcp = { version = "0.7.0", default-features = false, features = [ "socket-raw", "proto-ipv4",
+    "proto-ipv6", "socket-tcp", "ethernet"], optional = true }
+cortex-m = {version = "0.5", optional = true }
+
 # Optional dependencies for building examples
-stm32f4xx-hal = { version = "0.8", optional = true }
-cortex-m = { version = "0.5", optional = true }
-cortex-m-rt = { version = "0.6", optional = true }
-cortex-m-rtic = { version = "0.5.3", optional = true }
-panic-itm = { version = "0.4", optional = true }
-log = { version = "0.4", optional = true }
+[dev-dependencies]
+stm32f4xx-hal = { version = "0.8", features = ["stm32f407", "rt"] }
+cortex-m-rt = "0.6"
+cortex-m-rtic = "0.5.3"
+panic-itm = "0.4"
+log = "0.4"
 
 [features]
 smoltcp-phy = ["smoltcp"]
-nal = [ 
-    "embedded-time", "embedded-nal", "heapless",
-    "smoltcp-phy", "smoltcp/socket-tcp", "smoltcp/ethernet"
-]
 cortex-m-cpu = ["cortex-m"]
-# Example-based features
-smoltcp-examples = [
-    "smoltcp-phy", "smoltcp/socket-tcp", "smoltcp/ethernet"
-]
-tx_stm32f407 = [
-    "stm32f4xx-hal/stm32f407", "stm32f4xx-hal/rt", "cortex-m", "cortex-m-rtic", "cortex-m-cpu",
-    "panic-itm", "log"
-]
-tcp_stm32f407 = [
-    "stm32f4xx-hal/stm32f407", "stm32f4xx-hal/rt", "cortex-m", "cortex-m-rt", "cortex-m-rtic",
-    "cortex-m-cpu", "smoltcp-examples", "panic-itm", "log"]
 default = []
 
 [[example]]
 name = "tx_stm32f407"
-required-features = ["tx_stm32f407"]
+required-features = ["smoltcp", "cortex-m-cpu"]
 
 [[example]]
 name = "tcp_stm32f407"
-required-features = ["tcp_stm32f407"]
+required-features = ["smoltcp", "cortex-m-cpu"]
 
 [profile.release]
 codegen-units = 1
diff --git a/src/lib.rs b/src/lib.rs
index 014bf25..efb720f 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -12,9 +12,6 @@ pub mod tx;
 #[cfg(feature = "smoltcp")]
 pub mod smoltcp_phy;
 
-#[cfg(feature = "nal")]
-pub mod nal;
-
 /// Max raw frame array size
 pub const RAW_FRAME_LENGTH_MAX: usize = 1518;
 
diff --git a/src/nal.rs b/src/nal.rs
deleted file mode 100644
index f0d6dc5..0000000
--- a/src/nal.rs
+++ /dev/null
@@ -1,309 +0,0 @@
-use core::cell::RefCell;
-use core::convert::TryInto;
-use embedded_hal::{blocking::spi::Transfer, digital::v2::OutputPin};
-use embedded_nal as nal;
-pub use embedded_time as time;
-use heapless::{consts, Vec};
-use nal::nb;
-use smoltcp as net;
-use time::duration::*;
-
-#[derive(Debug)]
-pub enum NetworkError {
-    NoSocket,
-    ConnectionFailure,
-    ReadFailure,
-    WriteFailure,
-    Unsupported,
-    TimeFault,
-}
-
-pub type NetworkInterface<SPI, NSS> = net::iface::EthernetInterface<
-    'static,
-    crate::smoltcp_phy::SmoltcpDevice<crate::Enc424j600<SPI, NSS>>,
->;
-
-pub struct NetworkStack<'a, SPI, NSS, IntClock>
-where
-    SPI: 'static + Transfer<u8>,
-    NSS: 'static + OutputPin,
-    IntClock: time::Clock<T = u32>,
-{
-    network_interface: RefCell<NetworkInterface<SPI, NSS>>,
-    sockets: RefCell<net::socket::SocketSet<'a>>,
-    next_port: RefCell<u16>,
-    unused_handles: RefCell<Vec<net::socket::SocketHandle, consts::U16>>,
-    time_ms: RefCell<u32>,
-    last_update_instant: RefCell<Option<time::Instant<IntClock>>>,
-    clock: IntClock,
-    connection_timeout_ms: u32,
-}
-
-impl<'a, SPI, NSS, IntClock> NetworkStack<'a, SPI, NSS, IntClock>
-where
-    SPI: Transfer<u8>,
-    NSS: OutputPin,
-    IntClock: time::Clock<T = u32>,
-{
-    pub fn new(
-        interface: NetworkInterface<SPI, NSS>,
-        sockets: net::socket::SocketSet<'a>,
-        clock: IntClock,
-        connection_timeout_ms: u32,
-    ) -> Self {
-        let mut unused_handles: Vec<net::socket::SocketHandle, consts::U16> = Vec::new();
-        for socket in sockets.iter() {
-            unused_handles.push(socket.handle()).unwrap();
-        }
-        NetworkStack {
-            network_interface: RefCell::new(interface),
-            sockets: RefCell::new(sockets),
-            next_port: RefCell::new(49152),
-            unused_handles: RefCell::new(unused_handles),
-            time_ms: RefCell::new(0),
-            last_update_instant: RefCell::new(None),
-            clock,
-            connection_timeout_ms,
-        }
-    }
-
-    // Initiate or advance the timer, and return the duration in ms as u32.
-    fn update(&self) -> Result<u32, NetworkError> {
-        let mut duration_ms: u32 = 0;
-        // Check if it is the first time the stack has updated the time itself
-        let now = match *self.last_update_instant.borrow() {
-            // If it is the first time, do not advance time
-            // Simply store the current instant to initiate time updating
-            None => self.clock.try_now().map_err(|_| NetworkError::TimeFault)?,
-            // If it was updated before, advance time and update last_update_instant
-            Some(instant) => {
-                // Calculate elapsed time
-                let now = self.clock.try_now().map_err(|_| NetworkError::TimeFault)?;
-                let mut duration = now.checked_duration_since(&instant);
-                // Normally, the wrapping clock should produce a valid duration.
-                // However, if `now` is earlier than `instant` (e.g. because the main
-                // application cannot get a valid epoch time during initialisation,
-                // we should still produce a duration that is just 1ms.
-                if duration.is_none() {
-                    self.time_ms.replace(0);
-                    duration = Some(
-                        Milliseconds(1_u32)
-                            .to_generic::<u32>(IntClock::SCALING_FACTOR)
-                            .map_err(|_| NetworkError::TimeFault)?,
-                    );
-                }
-                let duration_ms_time: Milliseconds<u32> = duration
-                    .unwrap()
-                    .try_into()
-                    .map_err(|_| NetworkError::TimeFault)?;
-                duration_ms = *duration_ms_time.integer();
-                // Adjust duration into ms (note: decimal point truncated)
-                self.advance_time(duration_ms);
-                now
-            }
-        };
-        self.last_update_instant.replace(Some(now));
-        Ok(duration_ms)
-    }
-
-    fn advance_time(&self, duration_ms: u32) {
-        let time = self.time_ms.borrow().wrapping_add(duration_ms);
-        self.time_ms.replace(time);
-    }
-
-    // Poll on the smoltcp interface
-    fn poll(&self) -> Result<bool, NetworkError> {
-        match self.network_interface.borrow_mut().poll(
-            &mut self.sockets.borrow_mut(),
-            net::time::Instant::from_millis(*self.time_ms.borrow() as u32),
-        ) {
-            Ok(changed) => Ok(!changed),
-            Err(_e) => Ok(true),
-        }
-    }
-
-    fn get_ephemeral_port(&self) -> u16 {
-        // Get the next ephemeral port
-        let current_port = self.next_port.borrow().clone();
-        let (next, wrap) = self.next_port.borrow().overflowing_add(1);
-        *self.next_port.borrow_mut() = if wrap { 49152 } else { next };
-        return current_port;
-    }
-}
-impl<'a, SPI, NSS, IntClock> nal::TcpStack for NetworkStack<'a, SPI, NSS, IntClock>
-where
-    SPI: Transfer<u8>,
-    NSS: OutputPin,
-    IntClock: time::Clock<T = u32>,
-{
-    type TcpSocket = net::socket::SocketHandle;
-    type Error = NetworkError;
-    fn open(&self, _mode: nal::Mode) -> Result<Self::TcpSocket, Self::Error> {
-        match self.unused_handles.borrow_mut().pop() {
-            Some(handle) => {
-                // Abort any active connections on the handle.
-                let mut sockets = self.sockets.borrow_mut();
-                let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-                socket.abort();
-                Ok(handle)
-            }
-            None => Err(NetworkError::NoSocket),
-        }
-    }
-
-    fn connect(
-        &self,
-        handle: Self::TcpSocket,
-        remote: nal::SocketAddr,
-    ) -> Result<Self::TcpSocket, Self::Error> {
-        {
-            // If the socket has already been connected, ignore the connection
-            // request silently.
-            let mut sockets = self.sockets.borrow_mut();
-            let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-            if socket.state() == net::socket::TcpState::Established {
-                return Ok(handle);
-            }
-        }
-
-        {
-            let mut sockets = self.sockets.borrow_mut();
-            let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-            // abort() instead of close() prevents TcpSocket::connect() from
-            // raising an error
-            socket.abort();
-            match remote.ip() {
-                nal::IpAddr::V4(addr) => {
-                    let address = net::wire::Ipv4Address::from_bytes(&addr.octets()[..]);
-                    socket
-                        .connect((address, remote.port()), self.get_ephemeral_port())
-                        .map_err(|_| NetworkError::ConnectionFailure)?;
-                    net::wire::IpAddress::Ipv4(address)
-                }
-                nal::IpAddr::V6(addr) => {
-                    let address = net::wire::Ipv6Address::from_parts(&addr.segments()[..]);
-                    socket
-                        .connect((address, remote.port()), self.get_ephemeral_port())
-                        .map_err(|_| NetworkError::ConnectionFailure)?;
-                    net::wire::IpAddress::Ipv6(address)
-                }
-            }
-        };
-        // Blocking connect
-        // Loop to wait until the socket is staying established or closed,
-        // or the connection attempt has timed out.
-        let mut timeout_ms: u32 = 0;
-        loop {
-            {
-                let mut sockets = self.sockets.borrow_mut();
-                let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-                // TCP state at ESTABLISHED means there is connection, so
-                // simply return the socket.
-                if socket.state() == net::socket::TcpState::Established {
-                    return Ok(handle);
-                }
-                // TCP state at CLOSED implies that the remote rejected connection;
-                // In this case, abort the connection, and then return the socket
-                // for re-connection in the future.
-                if socket.state() == net::socket::TcpState::Closed {
-                    socket.abort();
-                    // TODO: Return Err(), but would require changes in quartiq/minimq
-                    return Ok(handle);
-                }
-            }
-
-            // Any TCP states other than CLOSED and ESTABLISHED are considered
-            // "transient", so this function should keep waiting and let smoltcp poll
-            // (e.g. for handling echo reqeust/reply) at the same time.
-            timeout_ms += self.update()?;
-            self.poll()?;
-
-            // Time out, and return the socket for re-connection in the future.
-            if timeout_ms > self.connection_timeout_ms {
-                // TODO: Return Err(), but would require changes in quartiq/minimq
-                return Ok(handle);
-            }
-        }
-    }
-
-    fn is_connected(&self, handle: &Self::TcpSocket) -> Result<bool, Self::Error> {
-        let mut sockets = self.sockets.borrow_mut();
-        let socket: &mut net::socket::TcpSocket = &mut *sockets.get(*handle);
-        Ok(socket.state() == net::socket::TcpState::Established)
-    }
-
-    fn write(&self, handle: &mut Self::TcpSocket, buffer: &[u8]) -> nb::Result<usize, Self::Error> {
-        let mut write_error = false;
-        let mut non_queued_bytes = &buffer[..];
-        while non_queued_bytes.len() != 0 {
-            let result = {
-                let mut sockets = self.sockets.borrow_mut();
-                let socket: &mut net::socket::TcpSocket = &mut *sockets.get(*handle);
-                let result = socket.send_slice(non_queued_bytes);
-                result
-            };
-            match result {
-                Ok(num_bytes) => {
-                    // If the buffer is completely filled, close the socket and
-                    // return an error
-                    if num_bytes == 0 {
-                        write_error = true;
-                        break;
-                    }
-                    // In case the buffer is filled up, push bytes into ethernet driver
-                    if num_bytes != non_queued_bytes.len() {
-                        self.update()?;
-                        self.poll()?;
-                    }
-                    // Process the unwritten bytes again, if any
-                    non_queued_bytes = &non_queued_bytes[num_bytes..]
-                }
-                Err(_) => {
-                    write_error = true;
-                    break;
-                }
-            }
-        }
-        if write_error {
-            // Close the socket to push it back to the array, for
-            // re-opening the socket in the future
-            self.close(*handle)?;
-            return Err(nb::Error::Other(NetworkError::WriteFailure));
-        }
-        Ok(buffer.len())
-    }
-
-    fn read(
-        &self,
-        handle: &mut Self::TcpSocket,
-        buffer: &mut [u8],
-    ) -> nb::Result<usize, Self::Error> {
-        // Enqueue received bytes into the TCP socket buffer
-        self.update()?;
-        self.poll()?;
-        {
-            let mut sockets = self.sockets.borrow_mut();
-            let socket: &mut net::socket::TcpSocket = &mut *sockets.get(*handle);
-            let result = socket.recv_slice(buffer);
-            match result {
-                Ok(num_bytes) => return Ok(num_bytes),
-                Err(_) => {}
-            }
-        }
-        // Close the socket to push it back to the array, for
-        // re-opening the socket in the future
-        self.close(*handle)?;
-        Err(nb::Error::Other(NetworkError::ReadFailure))
-    }
-
-    fn close(&self, handle: Self::TcpSocket) -> Result<(), Self::Error> {
-        let mut sockets = self.sockets.borrow_mut();
-        let socket: &mut net::socket::TcpSocket = &mut *sockets.get(handle);
-        socket.close();
-        let mut unused_handles = self.unused_handles.borrow_mut();
-        if unused_handles.iter().find(|&x| *x == handle).is_none() {
-            unused_handles.push(handle).unwrap();
-        }
-        Ok(())
-    }
-}