diff --git a/Cargo.lock b/Cargo.lock
index f968e2e..20eb915 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1813,7 +1813,7 @@ checksum = "7da8b5736845d9f2fcb837ea5d9e2628564b3b043a70948a3f0b778838c5fb4f"
 
 [[package]]
 name = "svc16"
-version = "0.6.0"
+version = "0.6.1"
 dependencies = [
  "anyhow",
  "clap",
diff --git a/Cargo.toml b/Cargo.toml
index 702c6fd..ac8a394 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "svc16"
-version = "0.6.0"
+version = "0.6.1"
 edition = "2021"
 authors = ["Jan Neuendorf"]
 description = "An emulator for a simple virtual computer"
diff --git a/src/engine.rs b/src/engine.rs
index 9cc8389..4b60e1b 100644
--- a/src/engine.rs
+++ b/src/engine.rs
@@ -36,8 +36,8 @@ pub enum EngineError {
     #[error("Division by zero")]
     ZeroDivision,
 
-    #[error("Invalid instruction")]
-    InvalidInstruction,
+    #[error("Invalid instruction {0}")]
+    InvalidInstruction(u16),
 }
 
 impl Engine {
@@ -216,7 +216,7 @@ impl Engine {
                 }
                 self.advance_inst_ptr();
             }
-            _ => return Err(EngineError::InvalidInstruction),
+            _ => return Err(EngineError::InvalidInstruction(opcode)),
         }
         Ok(())
     }
diff --git a/src/main.rs b/src/main.rs
index 6b26d4a..20747c2 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -87,8 +87,11 @@ fn main() -> Result<()> {
             let engine_start = Instant::now();
             while !engine.wants_to_sync() && ipf <= cli.max_ipf && !paused {
                 match engine.step() {
-                    Err(_) => {
-                        handle_event_loop_error(&elwt, "Invalid operation");
+                    Err(e) => {
+                        handle_event_loop_error(
+                            &elwt,
+                            format!("{} (after {} instructions)", e, ipf),
+                        );
                         return;
                     }
                     _ => {}