CB_CMD_OFFSET
PUTCB16(ncb, CB_CMD_OFFSET, cmd);
SYNCCB(lcb, CB_CMD_OFFSET, 2, DDI_DMA_SYNC_FORKERNEL);
PUTCB16(lcb, CB_CMD_OFFSET, GETCB16(lcb, CB_CMD_OFFSET) & ~CB_CMD_S);
SYNCCB(lcb, CB_CMD_OFFSET, 2, DDI_DMA_SYNC_FORDEV);