C======================================================================
      INTEGER FUNCTION TOWOFF(ICODE,TOWIND)
C======================================================================
C
C===Description:
C
C	This routine  calculate the offset in TOWE bank for a
C	certain CALL bank content.
C
C===Modulename:
C
C	C$JET:TOWOFF.CDF
C
C===Input Arguments:
C
C	ICODE : address given in CALL bank.
C	TOWIND : the TOWE bank first data address.
C
C===Output Arguments:
C
C	TOWOFF: Offset in the TOWE bank corresponding to the above address.
C
C===Author:
C
C	S. Kim
C
C===Revision History:
C
C	25-NOV-1986	Original Creation
C
C======================================================================
C
C===Implicit None Declaration:
C
      implicit none
C
C===Argument Decalarations:
C
      INTEGER ICODE, TOWIND
C
C===Global Parameter Declarations:
C
#include "inc/btmask.inc"
#include "inc/erlevl.inc"
#include "ybos/errcod.inc"
#include "inc/dscals.inc"
#include "inc/dstowe.inc"
#include "inc/bcs.inc"
#include "inc/jobsta.inc"
C
C===Local Variable Declarations:
C
	INTEGER INDBNK,IADDR
	INTEGER IETA, JCODE, LENBLK, TOWTYP
	INTEGER IFIRST, INEXT
C
C
C======================================================================
C
C===Start of Code:
C
C
C
C	 IPHI   = IAND(ICODE,MASK7)
C
	 IETA   = IAND(ISHFT(ICODE,-7),MASK7)
	 TOWTYP = TETTYP(IETA)
C
	 LENBLK = TETBLK(TOWTYP)  ! block length for this tower type
	 IFIRST  = IW(TOWIND + TENTOW +IETA) +TOWIND
	 INEXT   = IW(TOWIND + TENTOW +IETA +1) +TOWIND
C
	 IF(IFIRST.GE.INEXT) GOTO 1100     ! no data for this ring
	 IADDR = IFIRST
C
C-- Jump here for next tower
C
1099     CONTINUE
C
C-- Loop over tower blocks 
C
      	JCODE = IAND(IW(IADDR),MASK14)      ! mask off address
		IF( JCODE.EQ.ICODE ) THEN
		TOWOFF = IADDR - TOWIND
		RETURN
		ENDIF
C
C-- new address location of tower block
	  IADDR = IADDR + LENBLK
C
C-- see if we are finished with this annulus
	IF(IADDR.LT.INEXT-1) GOTO 1099
C
1100    CONTINUE
C
C---- Here for tower not present in TOWE
C
	TOWOFF = 0
C
C----------------------------------------------------------------------
C
C===Return to Caller:
C
      RETURN
      END