diff --git a/hash/ti99_cart.xml b/hash/ti99_cart.xml
index eb05a779acb..526ccf812b9 100644
--- a/hash/ti99_cart.xml
+++ b/hash/ti99_cart.xml
@@ -1076,7 +1076,7 @@
 	<publisher>&lt;unknown&gt;</publisher>
 	<info name="comment" value="BASIC programs stored in GROM: MotoCross-Awari-Carres-Hanoi. Allow for 20 seconds for games to start."/>
 	<part name="cart" interface="ti99_cart">
-		<feature name="pcb" value="standard"/>
+		<feature name="pcb" value="gromemu"/>
 		<dataarea name="grom_socket" size="0xa000">
 			<rom name="maxbasgg.bin" size="0xa000" crc="5318530d" sha1="12a378996ef61c6725cdf7f31042792de5374aa3" offset="0x0000" />
 		</dataarea>
@@ -1195,7 +1195,7 @@
 	<info name="version" value="4.0"/>
 	<info name="comment" value="Similar to TI Disk Manager"/>
 	<part name="cart" interface="ti99_cart">
-		<feature name="pcb" value="standard"/>
+		<feature name="pcb" value="gromemu"/>
 		<dataarea name="grom_socket" size="0x4000">
 			<rom name="dump_g.bin" size="0x4000" crc="dcd3433d" sha1="21fcba8e662786def43c94350459d2233377feb1" offset="0x0000" />
 		</dataarea>
diff --git a/src/mess/machine/ti99/gromport.c b/src/mess/machine/ti99/gromport.c
index e1b9c13cb33..1d26d6b6279 100644
--- a/src/mess/machine/ti99/gromport.c
+++ b/src/mess/machine/ti99/gromport.c
@@ -1840,6 +1840,7 @@ READ8Z_MEMBER(ti99_gromemu_cartridge::readz)
 		gromemureadz(space, offset, value, mem_mask);
 	else
 	{
+		if (m_rom_ptr == NULL) return;
 		if (m_rom_page==0)
 		{
 			*value = m_rom_ptr[offset & 0x1fff];