diff --git a/ponydos.asm b/ponydos.asm
index a8e9f30..4a705a0 100644
--- a/ponydos.asm
+++ b/ponydos.asm
@@ -454,7 +454,7 @@ mouse_y resw 1
 mouse_buttons resb 1
 
 mouse_column resb 1
-mouse_row resw 1
+mouse_row resb 1
 
 boot_disk resb 1