MC_RATE_16_Hz
bus_space_write_1(st, sh, 1, MC_BASE_32_KHz | MC_RATE_16_Hz);
bus_space_write_1(st, sh, 1, MC_BASE_32_KHz | MC_RATE_16_Hz);
bus_space_write_1(st, sh, 1, MC_BASE_32_KHz | MC_RATE_16_Hz);
(*sc->sc_mcwrite)(sc, MC_REGA, MC_BASE_32_KHz | MC_RATE_16_Hz);
bus_space_write_1(st, sh, 1, MC_BASE_32_KHz | MC_RATE_16_Hz);