CSR_DMASTAT
status = GETCSR(dca, CSR_DMASTAT);
PUTCSR(dca, CSR_DMASTAT, status & DMASTAT_INTERRUPTS);
status = GETCSR(dca, CSR_DMASTAT);
DBG(dca, DCHATTY, "STATUS = %x", GETCSR(dca, CSR_DMASTAT));