FXP_CB_STATUS_C
(txp->cb_status & FXP_CB_STATUS_C) != 0;
(txp->cb_status & FXP_CB_STATUS_C) != 0;
txp[i].cb_status = FXP_CB_STATUS_C | FXP_CB_STATUS_OK;
while (!(*status & FXP_CB_STATUS_C) && --i)