working tcp

pico/src/main.rs

@@ -2,6 +2,8 @@
 #![no_main]
 
 use arrayvec::ArrayVec;
+use core::convert::Infallible;
+use core::ops::Deref;
 use core::str::FromStr;
 use embassy_net::tcp::ConnectError;
 use embedded_io::ReadReady;
@@ -191,7 +193,7 @@ async fn main(spawner: Spawner) {
     info!("Connected to {:?}", socket.remote_endpoint());
 
     let delay = Duration::from_millis(100);
-    let mut buffer = ArrayVec::<u8, 512>::new();
+    let mut buffer = WriteBuffer::<1024>::new();
     loop {
         let in1 = in1.is_low();
         let in2 = in2.is_low();
@@ -201,7 +203,7 @@ async fn main(spawner: Spawner) {
         {
             use embedded_io::Write;
             let _ = core::writeln!(
-                &mut buffer[..],
+                &mut buffer,
                 "in1={} in2={} in3={} in4={} angle={}",
                 in1,
                 in2,
@@ -234,6 +236,45 @@ async fn main(spawner: Spawner) {
     }
 }
 
+struct WriteBuffer<const CAP: usize>(ArrayVec<u8, CAP>);
+
+impl<const CAP: usize> Deref for WriteBuffer<CAP> {
+    type Target = [u8];
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl<const CAP: usize> WriteBuffer<CAP> {
+    fn new() -> Self {
+        Self(ArrayVec::new())
+    }
+}
+
+impl<const CAP: usize> embedded_io::ErrorType for WriteBuffer<CAP> {
+    type Error = Infallible;
+}
+
+impl<const CAP: usize> embedded_io::Write for WriteBuffer<CAP> {
+    #[inline]
+    fn write(&mut self, buf: &[u8]) -> Result<usize, Self::Error> {
+        let _ = self.0.try_extend_from_slice(buf); //silently fails!
+        Ok(buf.len())
+    }
+
+    #[inline]
+    fn write_all(&mut self, buf: &[u8]) -> Result<(), Self::Error> {
+        self.write(buf)?;
+        Ok(())
+    }
+
+    #[inline]
+    fn flush(&mut self) -> Result<(), Self::Error> {
+        Ok(())
+    }
+}
+
 async fn wait_for_config(stack: Stack<'static>) -> embassy_net::StaticConfigV4 {
     loop {
         if let Some(config) = stack.config_v4() {