IM_RX_OVRN_INT
IM_EPH_INT | IM_RX_OVRN_INT | IM_RCV_INT | IM_TX_INT);
if (status & IM_RX_OVRN_INT) {
bus_space_write_1(bst, bsh, INTR_ACK_REG_B, IM_RX_OVRN_INT);