DP_UP_REQ_MSG_RDY
esi[1] &= DP_UP_REQ_MSG_RDY;
esi[1] &= (DP_DOWN_REP_MSG_RDY | DP_UP_REQ_MSG_RDY);
if (esi[1] & DP_UP_REQ_MSG_RDY) {
ack[1] |= DP_UP_REQ_MSG_RDY;
if (ack[1] & (DP_DOWN_REP_MSG_RDY | DP_UP_REQ_MSG_RDY))