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*DECK,NP$UPRU 
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      PROC NP$UPRU(OLDPTR,NEWPTR);
      BEGIN 
# 
**
*     1.  PROC NAME          AUTHOR          DATE 
* 
*         NP$UPRU            Y. C. YIP       02/16/1984 
* 
*     2.  FUNCTIONAL DESCRIPTION. 
* 
*         NP$UPRU UPDATES THE CURRENT INFORMATION POSITION IN 
*         THE DISK FET FOR BOTH SENDER AND RECEIVER.
* 
*     3.  METHOD USED.
* 
*         THE CURRENT INFORMATION IN THE DISK FET IS DETERMINED 
*         BY THE PRU NUMBER, WORD OFFSET WITHIN THE PRU NUMBER
*         AND THE DBIT THAT IS THE NEXT USABLE BIT POSITION IN THE
*         WORD OFFSET OF THE CURRENT PRU. DBIT IS ONLY USED BY THE
*         TRANSLATION SERVICE.
* 
*         FTT PRU IS COMPUTED BY THE CALCULATING THE DIFFERENCE 
*         OF THE NEWPTR AND THE OLDPTR WHICH ARE INPUT PARAMETERS 
*         USING THE FOLLOWING METHOD: 
*         FTTCURPRU = FTTCURPRU + (NEWPTR - OLDPTR)/64
*         WORD-OFFSET = REMAINDER OF (NEWPTR - OLDPTR)/64 
*         FTTDBIT = DBIT FROM CHARACTER MODE BUFFER 
* 
*     4.  ENTRY CONDITIONS: 
* 
*         NEWPTR = VALUE OF POINTER IN THE DISKFET. 
*         OLDPTR = VALUE OF OLDPOINTER IN THE DISKFET.
* 
* 
*     5.  EXIT CONDITIONS:  
* 
*         NEWPTR AND OLDPTR ARE NOT CHANGED.
*         FTTCURPRU, FTTWORD, AND FTTDBIT GET UPDATED.
* 
* 
# 
      ITEM WORDSKIP;                     # DIFFERENCE BETWEEN NEWPTR AND
                                           OLDPTR 
                                         #
      ITEM OLDPTR;                       # VALUE OF THE PREVIOUS PTR   #
      ITEM NEWPTR;                       # VALUE OF THE NEWPTR         #
      ITEM PRUEXCESS;                    # INCREMENT IN PRU NUMBER     #
 
      CONTROL EJECT;
# 
************************************************************************
*                                                                      *
*     CODE OF NP$UPRU BEGINS HERE                                      *
*                                                                      *
************************************************************************
# 
      P<FET$CIO> = FTTFETADR[FTTINDEX];  # PULL DISKFET TEMPLATE TO 
                                         FET ADDRESS IN FTT            #
      P<CMB> = FTTCMV$BLK[FTTINDEX];     # PULL CMB TEMPLATE TO        #
                                         # CMB ADDRESS IN FTT          #
      WORDSKIP = NEWPTR - OLDPTR;        # CALCULATE DIFFERENCE IN WORD#
 
      IF WORDSKIP LS 0                   # FET PPINTERS ALREADY WRAPPED#
      THEN                               # AROUND                      #
        BEGIN 
        WORDSKIP = WORDSKIP + FETLIM[0] - FETFIR[0];
        END                              # ADD THE FULL BUFFER SIZE    #
      FTTWORD[FTTINDEX] = FTTWORD[FTTINDEX] + WORDSKIP; 
                                         # CALCULATE NEW WORD          #
      PRUEXCESS = FTTWORD[FTTINDEX]/64;  # GET NEW PRU NUMBER          #
      IF PRUEXCESS GR 0                  # PRU INCREMENTED             #
      THEN
        BEGIN 
        FTTCURPRU[FTTINDEX] = 
        FTTCURPRU[FTTINDEX] + PRUEXCESS; # UPDATE FTTCURPRU            #
        FTTWORD[FTTINDEX] = FTTWORD[FTTINDEX] - PRUEXCESS*64; 
                                         # UPDATE FTTWORD              #
        END 
      FTTDBIT[FTTINDEX] = CMB$DBIT[0];   # UPDATE DBIT FROM CMB        #
      FTTMSTATE[FTTINDEX] = CMB$STATE[0]; # STORE LAST STATE OF        #
                                         #  TRANSLATION                #
      IF FTTOPCODE[FTTINDEX] EQ SEND     # FOR SENDER                  #
      THEN
        BEGIN 
        IF CMB$DBUF[0] EQ 1 AND FTTEOR[FTTINDEX]  # IF DISK BUFFER     #
                                         # EMPTY AND EOR               #
        THEN
          BEGIN 
          IF (NOT FTTEOI[FTTINDEX]) OR   # NOT EOI                     #
             (FTTEOI[FTTINDEX] AND
             ((NEWPTR NQ OLDPTR) OR (CMB$DBIT[0] NQ CMB$STEP[0])))
          THEN                           # OR EOI AND THERE IS NOTHING #
            BEGIN                        # IN THE DISK BUFFER          #
            FTTCURPRU[FTTINDEX] = FTTCURPRU[FTTINDEX] + 1;  # 1 PRU FOR#
                                         # EOR OR EOF                  #
            FTTWORD[FTTINDEX] = 0;       # INITIALIZE WORD COUNT TO 0  #
            FTTDBIT[FTTINDEX] = CMB$STEP[0];
            FTTMSTATE[0] = 0;            # CLEAR STATE OF TRANSLATION  #
            END 
          END 
        END 
      ELSE
        BEGIN                            # RECEIVER                    #
        IF CMB$NBUF[0] NQ 0 AND TBH$EOR[0]
        THEN                             # NETBUF EMPTY AND EORI       #
          BEGIN 
          IF (NOT TBH$EOI[0]) OR          # NOT EOI                    #
             (TBH$EOI[0] AND
            ((NEWPTR NQ OLDPTR) OR
            (CMB$DBIT[0] NQ WORDLENGTH - CMB$STEP[0]))) 
          THEN                           # OR EOI AND NOTHING IN THE   #
            BEGIN                        # THE DISK NUFFER             #
            FTTCURPRU[FTTINDEX] = FTTCURPRU[FTTINDEX] + 1;
            FTTWORD[FTTINDEX] = 0;       # INITIALIZE WORD COUNT TO 0  #
            FTTDBIT[FTTINDEX] = WORDLENGTH - CMB$STEP[0]; 
            FTTMSTATE[0] = 0;            # CLEAR STATE OF CONVERSION   #
            END 
          END 
        END 
      RETURN;                            # RETURN TO CALLER            #
      END                                # END OF PROC NP$UPRU         #
TERM
*ENDIF