format the same as display

src/wire/ethernet.rs

@@ -25,7 +25,6 @@ impl fmt::Display for EtherType {
 
 /// A six-octet Ethernet II address.
 #[derive(Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Clone, Copy, Default)]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct Address(pub [u8; 6]);
 
 impl Address {
@@ -79,6 +78,23 @@ impl fmt::Display for Address {
     }
 }
 
+#[cfg(feature = "defmt")]
+impl defmt::Format for Address {
+    fn format(&self, fmt: defmt::Formatter) {
+        let bytes = self.0;
+        defmt::write!(
+            fmt,
+            "{:02x}-{:02x}-{:02x}-{:02x}-{:02x}-{:02x}",
+            bytes[0],
+            bytes[1],
+            bytes[2],
+            bytes[3],
+            bytes[4],
+            bytes[5]
+        )
+    }
+}
+
 /// A read/write wrapper around an Ethernet II frame buffer.
 #[derive(Debug, Clone)]
 #[cfg_attr(feature = "defmt", derive(defmt::Format))]