diff --git a/main.asm b/main.asm
index 3581f20..68bb8fb 100644
--- a/main.asm
+++ b/main.asm
@@ -29,18 +29,58 @@ main:
 
     lp:
 
-    ; mov cx, 0
-    ; mov al, 0
-    ; mov dx, 320
-    ; mov bl, 200
-    ; mov bh, 0
+    call update_mouse
 
-    ;call gfx_rect
+    jmp lp
 
+jmp $ ; Halt
+
+update_mouse:
     cli
     mov bx, [mouseX]
     mov ax, [mouseY]
     sti
+    mov cx, [lastMouseX]
+    mov dx, [lastMouseY]
+
+    push bx
+    push ax
+    xor bx, cx
+    jnz .update
+    xor ax, dx
+    jnz .update
+
+    pop ax
+    pop bx
+    ret
+    .update:
+    pop ax
+    pop bx
+    call clear_last_mouse
+    call render_mouse
+
+    mov [lastMouseX], bx
+    mov [lastMouseY], ax
+    ret
+
+; cx = lastMouseX
+; dx = lastMouseY
+clear_last_mouse:
+    pusha
+
+    mov al, dl
+    mov dx, 11
+    mov bl, 18
+    mov bh, 0
+    call gfx_rect
+    
+    popa
+    ret
+
+; bx = mouseX
+; ax = mouseY
+render_mouse:
+    pusha
 
     mov dx, 0
     mov cx, 320
@@ -53,9 +93,8 @@ main:
     mov bl, 18
     call _gfx_blit0
 
-    jmp lp
-
-jmp $ ; Halt
+    popa
+    ret
     
 ; Libs
 %include "print_util.asm"
@@ -69,4 +108,7 @@ HELLO_WORLD:
 No:
     db 'No.', 0
 
+lastMouseX: dw 0
+lastMouseY: dw 0
+
 %include "gfx/gfxd_cursor.asm"
\ No newline at end of file
diff --git a/mouse_util.asm b/mouse_util.asm
index 3a96241..ca86449 100644
--- a/mouse_util.asm
+++ b/mouse_util.asm
@@ -186,9 +186,9 @@ mouse_callback:
     mov ax, 0
     .x0:
 
-    test bx, 0x8000
+    test dx, 0x8000
     jz .y0
-    mov bx, 0
+    mov dx, 0
     .y0:
 
     cmp ax, 320
@@ -196,9 +196,9 @@ mouse_callback:
     mov ax, 320
     .x1:
 
-    cmp bx, 200
+    cmp dx, 200
     jle .y1
-    mov bx, 200
+    mov dx, 200
     .y1:
 
     ; Status