diff --git a/src/mame/drivers/ataxx.cpp b/src/mame/drivers/ataxx.cpp
index 6cf04fe60aa..4c73b146336 100644
--- a/src/mame/drivers/ataxx.cpp
+++ b/src/mame/drivers/ataxx.cpp
@@ -50,7 +50,7 @@ static ADDRESS_MAP_START( master_map_program, AS_PROGRAM, 8, leland_state )
 	AM_RANGE(0x0000, 0x1fff) AM_ROM
 	AM_RANGE(0x2000, 0x9fff) AM_ROMBANK("bank1")
 	AM_RANGE(0xa000, 0xdfff) AM_ROMBANK("bank2") AM_WRITE(ataxx_battery_ram_w) AM_SHARE("battery")
-	AM_RANGE(0xe000, 0xf7ff) AM_RAM
+	AM_RANGE(0xe000, 0xf7ff) AM_RAM AM_SHARE("mainram")
 	AM_RANGE(0xf800, 0xffff) AM_READWRITE(ataxx_paletteram_and_misc_r, ataxx_paletteram_and_misc_w) AM_SHARE("palette")
 ADDRESS_MAP_END