diff --git a/src/card.rs b/src/card.rs
index d58b100..e7dd331 100644
--- a/src/card.rs
+++ b/src/card.rs
@@ -149,7 +149,6 @@ pub trait Mmu: Debug {
     ) -> NullableResult<u32, BusError>;
 }
 
-
 #[allow(dead_code)]
 pub const fn u64_set_be_byte(val: u64, idx: u8, byte: u8) -> u64 {
     let mut bytes = val.to_be_bytes();
diff --git a/src/mmu.rs b/src/mmu.rs
index 481e5ea..36e7867 100644
--- a/src/mmu.rs
+++ b/src/mmu.rs
@@ -143,32 +143,28 @@ impl Card for MmuCard {
 impl Display for MmuCard {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let q1 = if self.map_frames_enabled[0] {
-            Some(self.map_frames[0])
+            format!("{:#x}", self.map_frames[0])
         } else {
-            None
+            "disabled".to_string()
         };
         let q2 = if self.map_frames_enabled[1] {
-            Some(self.map_frames[1])
+            format!("{:#x}", self.map_frames[1])
         } else {
-            None
+            "disabled".to_string()
         };
         let q3 = if self.map_frames_enabled[2] {
-            Some(self.map_frames[2])
+            format!("{:#x}", self.map_frames[2])
         } else {
-            None
+            "disabled".to_string()
         };
         let q4 = if self.map_frames_enabled[3] {
-            Some(self.map_frames[3])
+            format!("{:#x}", self.map_frames[3])
         } else {
-            None
+            "disabled".to_string()
         };
         f.write_fmt(format_args!(
-            "MMU card, {} (Q1: {:?}, Q2: {:?}, Q3: {:?}, Q4: {:?})",
+            "MMU card, {} (Q1: {q1}, Q2: {q2}, Q3: {q3}, Q4: {q4})",
             if self.enabled { "enabled" } else { "disabled" },
-            q1,
-            q2,
-            q3,
-            q4
         ))
     }
 }