ATPPC_SPP_DTR
dtr_sav = bus_space_read_1(iot, ioh, ATPPC_SPP_DTR);
bus_space_write_1(iot, ioh, ATPPC_SPP_DTR, 0xaa);
if (bus_space_read_1(iot, ioh, ATPPC_SPP_DTR) != 0xaa) {
bus_space_write_1(iot, ioh, ATPPC_SPP_DTR, 0x55);
if (bus_space_read_1(iot, ioh, ATPPC_SPP_DTR) != 0x55) {
bus_space_write_1(iot, ioh, ATPPC_SPP_DTR, dtr_sav);
ATPPC_SPP_DTR)
(atppc)->sc_ioh, ATPPC_SPP_DTR, (byte))