diff --git a/src/backplane.rs b/src/backplane.rs
index 5f1baac..4256eca 100644
--- a/src/backplane.rs
+++ b/src/backplane.rs
@@ -150,8 +150,8 @@ impl Backplane {
     pub fn read_word(&self, address: u32) -> Result<u16, BusError> {
         self.mem_helper(
             address,
-            |mut card| card.read_word(address),
-            |mut card| card.read_word_io(address as u8),
+            |address, mut card| card.read_word(address),
+            |address, mut card| card.read_word_io(address as u8),
             false,
             false,
         )
@@ -160,8 +160,8 @@ impl Backplane {
     pub fn read_byte(&self, address: u32) -> Result<u8, BusError> {
         self.mem_helper(
             address,
-            |mut card| card.read_byte(address),
-            |mut card| card.read_byte_io(address as u8),
+            |address, mut card| card.read_byte(address),
+            |address, mut card| card.read_byte_io(address as u8),
             false,
             false,
         )
@@ -170,8 +170,8 @@ impl Backplane {
     pub fn write_word(&self, address: u32, data: u16) -> Result<(), BusError> {
         self.mem_helper(
             address,
-            |mut card| card.write_word(address, data),
-            |mut card| card.write_word_io(address as u8, data),
+            |address, mut card| card.write_word(address, data),
+            |address, mut card| card.write_word_io(address as u8, data),
             false,
             true,
         )
@@ -180,8 +180,8 @@ impl Backplane {
     pub fn write_byte(&self, address: u32, data: u8) -> Result<(), BusError> {
         self.mem_helper(
             address,
-            |mut card| card.write_byte(address, data),
-            |mut card| card.write_byte_io(address as u8, data),
+            |address, mut card| card.write_byte(address, data),
+            |address, mut card| card.write_byte_io(address as u8, data),
             false,
             true,
         )
@@ -190,8 +190,8 @@ impl Backplane {
     pub fn read_word_phys(&self, address: u32) -> Result<u16, BusError> {
         self.mem_helper(
             address,
-            |mut card| card.read_word(address),
-            |mut card| card.read_word_io(address as u8),
+            |address, mut card| card.read_word(address),
+            |address, mut card| card.read_word_io(address as u8),
             true,
             false,
         )
@@ -201,8 +201,8 @@ impl Backplane {
     pub fn read_byte_phys(&self, address: u32) -> Result<u8, BusError> {
         self.mem_helper(
             address,
-            |mut card| card.read_byte(address),
-            |mut card| card.read_byte_io(address as u8),
+            |address, mut card| card.read_byte(address),
+            |address, mut card| card.read_byte_io(address as u8),
             true,
             false,
         )
@@ -212,8 +212,8 @@ impl Backplane {
     pub fn write_word_phys(&self, address: u32, data: u16) -> Result<(), BusError> {
         self.mem_helper(
             address,
-            |mut card| card.write_word(address, data),
-            |mut card| card.write_word_io(address as u8, data),
+            |address, mut card| card.write_word(address, data),
+            |address, mut card| card.write_word_io(address as u8, data),
             true,
             true,
         )
@@ -223,8 +223,8 @@ impl Backplane {
     pub fn write_byte_phys(&self, address: u32, data: u8) -> Result<(), BusError> {
         self.mem_helper(
             address,
-            |mut card| card.write_byte(address, data),
-            |mut card| card.write_byte_io(address as u8, data),
+            |address, mut card| card.write_byte(address, data),
+            |address, mut card| card.write_byte_io(address as u8, data),
             true,
             true,
         )
@@ -239,8 +239,8 @@ impl Backplane {
         write: bool,
     ) -> Result<T, BusError>
     where
-        M: FnMut(RefMut<'_, dyn Card>) -> NullableResult<T, BusError>,
-        I: FnMut(RefMut<'_, dyn Card>) -> NullableResult<T, BusError>,
+        M: FnMut(u32, RefMut<'_, dyn Card>) -> NullableResult<T, BusError>,
+        I: FnMut(u32, RefMut<'_, dyn Card>) -> NullableResult<T, BusError>,
     {
         let address = if bypass_mmu {
             address
@@ -262,14 +262,14 @@ impl Backplane {
             (0..=0x00fe_ffff) | (0x0100_0000..=0xffff_ffff) => self
                 .cards
                 .iter()
-                .try_find_map(|card| mem_func(card.borrow_mut()))
+                .try_find_map(|card| mem_func(address, card.borrow_mut()))
                 .result(BusError),
             (0x00ff_0000..=0x00ff_00ff) => Ok(T::default()),
             (0x00ff_0100..=0x00ff_ffff) => self
                 .cards
                 .get(((address >> 8) as u8 - 1) as usize)
                 .map_or(Ok(T::default()), |card| {
-                    io_func(card.borrow_mut())
+                    io_func(address, card.borrow_mut())
                         .optional_result()
                         .unwrap_or(Ok(T::default()))
                 }),