diff --git a/src/backplane.rs b/src/backplane.rs
index 46cfba2..01021eb 100644
--- a/src/backplane.rs
+++ b/src/backplane.rs
@@ -137,6 +137,7 @@ impl Backplane {
     }
 
     pub fn reset(&self) {
+        self.io_at_top_16mb.store(true, Ordering::Relaxed);
         for card in &self.cards {
             card.borrow_mut().reset();
         }