diff --git a/src/mame/drivers/jrpacman.c b/src/mame/drivers/jrpacman.c
index 611b4bdc33d..e1e26f37e5d 100644
--- a/src/mame/drivers/jrpacman.c
+++ b/src/mame/drivers/jrpacman.c
@@ -109,10 +109,6 @@ class jrpacman_state : public pacman_state
 public:
 	jrpacman_state(running_machine &machine, const driver_device_config_base &config)
 		: pacman_state(machine, config) { }
-
-	UINT8 *spriteram;
-	UINT8 *spriteram2;
-	size_t spriteram_size;
 };
 
 
@@ -135,14 +131,14 @@ static ADDRESS_MAP_START( main_map, ADDRESS_SPACE_PROGRAM, 8 )
 	AM_RANGE(0x0000, 0x3fff) AM_ROM
 	AM_RANGE(0x4000, 0x47ff) AM_RAM_WRITE(jrpacman_videoram_w) AM_BASE_MEMBER(jrpacman_state, videoram)
 	AM_RANGE(0x4800, 0x4fef) AM_RAM
-	AM_RANGE(0x4ff0, 0x4fff) AM_RAM AM_BASE_SIZE_MEMBER(jrpacman_state, spriteram, spriteram_size)
+	AM_RANGE(0x4ff0, 0x4fff) AM_RAM AM_BASE_SIZE_GENERIC(spriteram)
 	AM_RANGE(0x5000, 0x503f) AM_READ_PORT("P1")
 	AM_RANGE(0x5000, 0x5000) AM_WRITE(interrupt_enable_w)
 	AM_RANGE(0x5001, 0x5001) AM_DEVWRITE("namco", pacman_sound_enable_w)
 	AM_RANGE(0x5003, 0x5003) AM_WRITE(pacman_flipscreen_w)
 	AM_RANGE(0x5040, 0x507f) AM_READ_PORT("P2")
 	AM_RANGE(0x5040, 0x505f) AM_DEVWRITE("namco", pacman_sound_w)
-	AM_RANGE(0x5060, 0x506f) AM_WRITEONLY AM_BASE_MEMBER(jrpacman_state, spriteram2)
+	AM_RANGE(0x5060, 0x506f) AM_WRITEONLY AM_BASE_GENERIC(spriteram2)
 	AM_RANGE(0x5070, 0x5070) AM_WRITE(pengo_palettebank_w)
 	AM_RANGE(0x5071, 0x5071) AM_WRITE(pengo_colortablebank_w)
 	AM_RANGE(0x5073, 0x5073) AM_WRITE(jrpacman_bgpriority_w)