diff --git a/src/hardware/vga.h b/src/hardware/vga.h
index 1ebc643f..88e9ce4d 100644
--- a/src/hardware/vga.h
+++ b/src/hardware/vga.h
@@ -243,6 +243,7 @@ void VGA_SetupSEQ(void);
 
 /* Some Support Functions */
 void VGA_DACSetEntirePalette(void);
+void VGA_StartRetrace(void);
 
 extern VGA_Type vga;
 extern Bit8u vga_rom_08[256 * 8];