GH-3: Update README as well

README.md

@@ -3,25 +3,33 @@
 Below some really basic usage how I am ca using it:
 
 ```rust
-    let spi = ...; // SPI interface to use
-    let cs : OutputPin = ...; // chip select
-    
-    let mut w5500 = W5500::new(spi, cs).unwrap();
+    let mut w5500: Option<W5500> = W5500::with_initialisation(
+        &mut cs_w5500, // borrowed for whole W5500 lifetime
+        &mut spi, // borrowed for call to `with_initialisation` only
+        OnWakeOnLan::Ignore,
+        OnPingRequest::Respond,
+        ConnectionType::Ethernet,
+        ArpResponses::Cache,
+    )
+    .ok();
 
-    w5500.set_mode(false, false, false, false).unwrap();
-    // using a 'locally administered' MAC address
-    w5500.set_mac(&MacAddress::new(0x02, 0x01, 0x02, 0x03, 0x04, 0x05)).unwrap();
-    w5500.set_ip(&IpAddress::new(192, 168, 0, 222)).unwrap();
-    w5500.set_subnet(&IpAddress::new(255, 255, 255, 0)).unwrap();
-    w5500.set_gateway(&IpAddress::new(192, 168, 0, 1)).unwrap();
+    let mut udp_server_socket: Option<UdpSocket> = w5500.as_mut().and_then(|w5500| {
+        let mut w5500: ActiveW5500<_> = w5500.activate(&mut spi).ok()?;
+        let socket0: UninitializedSocket = w5500.take_socket(Socket::Socket0)?;
+        (&mut w5500, socket0).try_into_udp_server_socket(1234).ok()
+    });
 
-    w5500.listen_udp(Socket::Socket1, 51).unwrap();
-    let buffer = [u8; 2048];
-    
-    if let Some((ip, port, size)) = w5500.try_receive_udp(socket_rcv, &mut buffer).unwrap() {
-        let (request_buffer, response_buffer) = buffer.split_mut_at(size);
-        // ...
+    let mut buffer = [0u8; 256];
+    if let (Some(ref mut w5500), Some(ref socket)) = (
+        w5500.as_mut().and_then(w5500.activate(&mut spi).ok()),
+        udp_server_socket,
+    ) {
+        if let Ok(Some((ip, port, len))) = (w5500, socket).receive(&mut buffer[..]) {
+            let (request_buffer, response_buffer) = buffer.split_mut_at(len);
 
-        w5500.send_udp(Socket::Socket0, 50, &ip, port, &response_buffer[..response_size]).unwrap();
+            //...
+
+            (w5500, socket).blocking_send(ip, port, 1234, response_buffer[..response_len]).unwrap();
+        }
     }
 ```