ASC_IOP_REG_DC0
#define ASC_READ_CHIP_DC0(iot, ioh) bus_space_read_2((iot), (ioh), ASC_IOP_REG_DC0)
#define ASC_WRITE_CHIP_DC0(iot, ioh) bus_space_write_2((iot), (ioh), ASC_IOP_REG_DC0, data)