diff --git a/src/pipe.rs b/src/pipe.rs
index 2e84d1a..debd5de 100644
--- a/src/pipe.rs
+++ b/src/pipe.rs
@@ -281,7 +281,7 @@ where
             State::Idle => {
                 // invariant: BUFFER_SIZE >= PACKET_SIZE
                 match command.chain() {
-                    Chain::BeginsAndEnds => {
+                    Ok(Chain::BeginsAndEnds) => {
                         info!("begins and ends");
                         self.reset_interchange();
                         let Some(message) = self.interchange.request_mut() else {
@@ -299,7 +299,7 @@ where
                         self.state = State::Processing;
                         // self.send_empty_datablock();
                     }
-                    Chain::Begins => {
+                    Ok(Chain::Begins) => {
                         info!("begins");
                         self.reset_interchange();
                         let Some(message) = self.interchange.request_mut() else {
@@ -316,6 +316,10 @@ where
                         self.state = State::Receiving;
                         self.send_empty_datablock(Chain::ExpectingMore);
                     }
+                    Err(_) => {
+                        error!("Unknown chain");
+                        self.reset_state();
+                    }
                     _ => {
                         error!("unexpectedly in idle state");
                         self.reset_state();
@@ -324,7 +328,7 @@ where
             }
 
             State::Receiving => match command.chain() {
-                Chain::Continues => {
+                Ok(Chain::Continues) => {
                     info!("continues");
                     let Some(message) = self.interchange.request_mut() else {
                         error!("Interchange is busy");
@@ -338,7 +342,7 @@ where
                     }
                     self.send_empty_datablock(Chain::ExpectingMore);
                 }
-                Chain::Ends => {
+                Ok(Chain::Ends) => {
                     info!("ends");
                     let Some(message) = self.interchange.request_mut() else {
                         error!("Interchange is busy");
@@ -353,6 +357,10 @@ where
                     self.call_app();
                     self.state = State::Processing;
                 }
+                Err(_) => {
+                    error!("Unknown chain");
+                    self.reset_state();
+                }
                 _ => {
                     error!("unexpectedly in receiving state");
                     self.reset_state();
@@ -368,7 +376,7 @@ where
             }
 
             State::Sending => match command.chain() {
-                Chain::ExpectingMore => {
+                Ok(Chain::ExpectingMore) => {
                     self.prime_outbox();
                 }
                 _chain => {
diff --git a/src/types/packet.rs b/src/types/packet.rs
index 9011e6e..c6e3491 100644
--- a/src/types/packet.rs
+++ b/src/types/packet.rs
@@ -61,17 +61,20 @@ pub trait PacketWithData: Packet {
     }
 }
 
+#[derive(Debug, Default, Clone, Copy)]
+pub struct UnknownChaining;
+
 pub trait ChainedPacket: Packet {
     #[inline(always)]
-    fn chain(&self) -> Chain {
+    fn chain(&self) -> Result<Chain, UnknownChaining> {
         let level_parameter = u16::from_le_bytes(self[8..10].try_into().unwrap());
         match level_parameter {
-            0 => Chain::BeginsAndEnds,
-            1 => Chain::Begins,
-            2 => Chain::Ends,
-            3 => Chain::Continues,
-            0x10 => Chain::ExpectingMore,
-            _ => panic!("invalid power select parameter"),
+            0 => Ok(Chain::BeginsAndEnds),
+            1 => Ok(Chain::Begins),
+            2 => Ok(Chain::Ends),
+            3 => Ok(Chain::Continues),
+            0x10 => Ok(Chain::ExpectingMore),
+            _ => Err(UnknownChaining),
         }
     }
 }