diff --git a/src/mess/drivers/c64.c b/src/mess/drivers/c64.c
index 01897ecb2b0..0fd2ae952d6 100644
--- a/src/mess/drivers/c64.c
+++ b/src/mess/drivers/c64.c
@@ -1399,8 +1399,8 @@ static MACHINE_CONFIG_START( pal_gs, c64gs_state )
 	MCFG_MOS6526_IRQ_CALLBACK(WRITELINE(c64_state, cia1_irq_w))
 	MCFG_MOS6526_CNT_CALLBACK(DEVWRITELINE(PET_USER_PORT_TAG, pet_user_port_device, write_4))
 	MCFG_MOS6526_SP_CALLBACK(DEVWRITELINE(PET_USER_PORT_TAG, pet_user_port_device, write_5))
-	MCFG_MOS6526_PA_INPUT_CALLBACK(READ8(c64_state, cia1_pa_r))
-	MCFG_MOS6526_PB_INPUT_CALLBACK(READ8(c64_state, cia1_pb_r))
+	MCFG_MOS6526_PA_INPUT_CALLBACK(READ8(c64gs_state, cia1_pa_r))
+	MCFG_MOS6526_PB_INPUT_CALLBACK(READ8(c64gs_state, cia1_pb_r))
 	MCFG_MOS6526_PB_OUTPUT_CALLBACK(WRITE8(c64_state, cia1_pb_w))
 	MCFG_DEVICE_ADD(MOS6526_2_TAG, MOS6526, XTAL_17_734472MHz/18)
 	MCFG_MOS6526_TOD(50)