NCR_700_SLOT_MAGIC
if((slot->state & NCR_700_SLOT_MASK) != NCR_700_SLOT_MAGIC) {
#define NCR_700_SLOT_FREE (0|NCR_700_SLOT_MAGIC) /* slot may be used */
#define NCR_700_SLOT_BUSY (1|NCR_700_SLOT_MAGIC) /* slot has command active on HA */
#define NCR_700_SLOT_QUEUED (2|NCR_700_SLOT_MAGIC) /* slot has command to be made active on HA */