SUBROUTINE INIT (BLK, ISUB, IBEG, IREC, PC)
C
C	ROBERT WATSON
C	CISCO, INC.
C	(918)665-2110
C	4135 S. 100TH E. AVE.
C	TULSA OK 74145
C
C	THIS PROGRAM HAS BEEN DONATED TO THE PUBLIC DOMAIN
C	AND IS NOT TO BE COPYRIGHTED.
C
	INTEGER*4	IBEG,		PC,		RO
	INTEGER*2	BLK(256),	ROREC
	IREC = 1
	CALL FILL (BLK, IREC, ISUB, PC)
	IF (BLK(76) .EQ. 0) GO TO 10	!PC OF READONLY SECTION OF TASK
	RO = BLK(76)
	RO = (RO .AND. "177777)
	ROREC = BLK(75) + IREC		!REC. NO. OF 1ST RO BLOCK
	ISUB = -1			!CODE TO INITIALIZE RO PTRS
	CALL FILL (BLK, ROREC, ISUB, RO)
	ISUB = 0
	IF (IBEG .LT. RO) GO TO 10	!WAS A RO ADDR. REQUESTED?
	PC = RO
	IREC = IREC + BLK(75)
	CALL FILL (BLK, IREC, ISUB, PC)	!POSITION ON 1ST RO WORD
	IF (IBEG .EQ. PC) RETURN
	PC = IBEG
	IBEG = (IBEG - RO) + 2		!OFFSET TO REQUESTED ADDR.
	GO TO 20
10	IREC = BLK(70)
	CALL FILL (BLK, IREC, ISUB, PC)
	IZERO = (BLK(62) * 32) + 1	!SUBSCR. OF VIR. ZERO WD
20	INO = IBEG / 512		!NO. FULL BLKS BEFORE IBEG
	IF (INO .LE. 0) GO TO 30
	IREC = IREC + INO
	CALL FILL (BLK, IREC, ISUB, PC)
30	INO = (IBEG .AND. "777)		!BYTE DISPL. IN THIS BLK
	INO = INO / 2			!WD DISPL.
	ISUB = IZERO + INO		!SUBSCR. OF IBEG
	IF (ISUB .LE. 256) RETURN	!DISPL. TO VIR. ZERO COULD OVERFLOW
	INO = ISUB - 256		!SAVE DIFFERENCE
	IREC = IREC + 1
	CALL FILL (BLK, IREC, ISUB, PC)
	ISUB = INO
	RETURN
	END