diff --git a/src/app_dio.rs b/src/app_dio.rs
index 39e27ed..a55ba37 100644
--- a/src/app_dio.rs
+++ b/src/app_dio.rs
@@ -1,29 +1,65 @@
 // Print debug support
-use crate::print_debug_message;
+use crate::{api_dio::PicohaDioRequest, print_debug_message};
 use core::fmt::Write;
 
 // USB Communications Class Device support
 use usbd_serial::SerialPort;
 
+// Size of internal buffers
+const BUFFER_CAPACITY: usize = 64;
+
 /// Application Digital I/O
 pub struct AppDio {
-    // ...
+    // Accumulated incoming data buffer
+    in_buf: [u8; BUFFER_CAPACITY],
+    // Keep track of number of data in the buffer
+    in_buf_size: usize,
+    // Decode buffer
+    decode_buffer: [u8; BUFFER_CAPACITY],
 }
 
 impl AppDio {
     pub fn new() -> Self {
         AppDio {
-            // ...
+            in_buf: [0u8; 64],
+            in_buf_size: 0,
+            decode_buffer: [0u8; 64],
         }
     }
 
+    /// Accumulate new data
+    fn accumulate_new_data(&mut self, data: &[u8]) {
+        // Compute indexes
+        let data_len = data.len();
+        let i_from = self.in_buf_size;
+        let i_to = self.in_buf_size + data_len;
+
+        // Copy data to the buffer
+        self.in_buf[i_from..i_to].clone_from_slice(&data);
+
+        // Update the buffer size
+        self.in_buf_size += data_len;
+    }
+
+    /// Try to decode a request from the incoming data buffer
+    ///
+    fn try_to_decode_request(&self) -> Option<PicohaDioRequest> {
+        let mut slip_decoder = serial_line_ip::Decoder::new();
+
+        // match slip_decoder.decode(&cmd_buf[..cmd_buf_size], &mut decoded_buffer) {
+        //     Ok((input_bytes_processed, output_slice, is_end_of_packet)) => {
+
+        None
+    }
+
+    /// Process incoming data
+    ///
     pub fn process_incoming_data(
         &mut self,
         serial: &mut SerialPort<rp2040_hal::usb::UsbBus>,
         data: &[u8],
     ) {
-        print_debug_message!("Received data: {:?}", data);
-
-        // ...
+        print_debug_message!("+ recieved data: {:?}", data);
+        self.accumulate_new_data(data);
     }
 }
diff --git a/src/main.rs b/src/main.rs
index 0e15076..f1d541f 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -216,44 +216,6 @@ unsafe fn main() -> ! {
                 }
                 Ok(count) => {
                     app.process_incoming_data(&mut serial, &buf[..count]);
-                    // command_buffer[..count].iter().for_each(|b| {
-
-                    // });
-
-                    // cmd_buf[cmd_buf_size..count].clone_from_slice(&buf);
-
-                    // Usage:
-                    print_debug_message!("Received {} bytes, {}", count, cmd_buf.len());
-
-                    let oooo = &buf[..count];
-                    // writeln!(&mut message, "Received {:?}", oooo).unwrap();
-                    // DEBUG_UART
-                    //     .as_ref()
-                    //     .unwrap()
-                    //     .write_full_blocking(message.as_bytes());
-
-                    {
-                        let (left, right) = cmd_buf.split_at_mut(cmd_buf_size);
-
-                        // writeln!(&mut message, "left {}, right {}", left.len(), right.len())
-                        //     .unwrap();
-                        // DEBUG_UART
-                        //     .as_ref()
-                        //     .unwrap()
-                        //     .write_full_blocking(message.as_bytes());
-
-                        right[..count].clone_from_slice(&buf[..count]);
-
-                        cmd_buf_size += count;
-                    }
-
-                    // writeln!(&mut message, "total {:?}", cmd_buf).unwrap();
-                    // DEBUG_UART
-                    //     .as_ref()
-                    //     .unwrap()
-                    //     .write_full_blocking(message.as_bytes());
-
-                    // cmd_buf_size += count;
 
                     //
                     let mut slip_decoder = serial_line_ip::Decoder::new();