diff --git a/src/mame/drivers/harddriv.cpp b/src/mame/drivers/harddriv.cpp
index 983517a5acc..af2d95ec333 100644
--- a/src/mame/drivers/harddriv.cpp
+++ b/src/mame/drivers/harddriv.cpp
@@ -652,6 +652,7 @@ ADDRESS_MAP_END
 static ADDRESS_MAP_START( adsp_program_map, AS_PROGRAM, 32, harddriv_state )
 	ADDRESS_MAP_UNMAP_HIGH
 	AM_RANGE(0x0000, 0x1fff) AM_RAM AM_SHARE("adsp_pgm_memory")
+	AM_RANGE(0x2000, 0x3fff) AM_READNOP // ROM?
 ADDRESS_MAP_END