diff --git a/src/mame/drivers/astrocde.cpp b/src/mame/drivers/astrocde.cpp
index b0a4c2bcab0..73b32d70563 100644
--- a/src/mame/drivers/astrocde.cpp
+++ b/src/mame/drivers/astrocde.cpp
@@ -1721,7 +1721,7 @@ DRIVER_INIT_MEMBER(astrocde_state,gorf)
 {
 	m_video_config = AC_SOUND_PRESENT | AC_LIGHTPEN_INTS | AC_STARS;
 	m_maincpu->space(AS_IO).install_read_handler(0x15, 0x15, 0, 0xf000, 0x0f00, read8_delegate(FUNC(astrocde_state::gorf_io_1_r), this));
-	m_maincpu->space(AS_IO).install_read_handler(0x16, 0x16, 0, 0xf000, 0xff00, read8_delegate(FUNC(astrocde_state::gorf_io_2_r), this));
+	m_maincpu->space(AS_IO).install_read_handler(0x16, 0x16, 0, 0xf000, 0x0f00, read8_delegate(FUNC(astrocde_state::gorf_io_2_r), this));
 	m_maincpu->space(AS_IO).install_read_handler(0x17, 0x17, 0, 0x0000, 0xff00, read8_delegate(FUNC(astrocde_state::gorf_speech_r), this));
 }