INTR_LATCH
if ((status & INTR_LATCH) == 0) {
if ((status & INTR_LATCH) == 0) {
(status & (INTR_LATCH | ALL_INTERRUPTS)));
bus_space_write_2(iot, ioh, ELINK_COMMAND, ACK_INTR | INTR_LATCH);
if ((stat & INTR_LATCH) == 0) {
(stat & (XL_WATCHED_INTERRUPTS | INTR_LATCH)));
bus_space_write_2(iot, ioh, ELINK_COMMAND, ACK_INTR | INTR_LATCH);