subroutine bits71 (iw7, imdf, itr, iit, iiz)
c
c-----------------------------------------------------------------------
c
c     This routine setup the masks to determine flags from word 7/1 only
c
c     Do not change these integer*2s to integer*4s
c-----------------------------------------------------------------------
c
      logical*1 iw7
c
      integer*2 iit, iiz, imask, imdf, itr, nbsht
c
c-----------------------------------------------------------------------
c     *** determine the mask and bit shift for imdf flag ***
c-----------------------------------------------------------------------
c
      imask = '200'O
      nbsht = 1
      call bitmsk (iw7, imask, nbsht, imdf)
c
c-----------------------------------------------------------------------
c     *** determine the mask and bit shift for itr flag ***
c-----------------------------------------------------------------------
c
      imask = '140'O
      nbsht = 3
      call bitmsk (iw7, imask, nbsht, itr)
c
c-----------------------------------------------------------------------
c     *** determine the mask and bit shift for the iit flag ***
c-----------------------------------------------------------------------
c
      imask = '30'O
      nbsht = 5
      call bitmsk (iw7, imask, nbsht, iit)
c
c-----------------------------------------------------------------------
c     *** determine the mask and bit shift for the iiz flag ***
c-----------------------------------------------------------------------
c
      imask = 7
      nbsht = 8
      call bitmsk (iw7, imask, nbsht, iiz)
c
c-----------------------------------------------------------------------
c-----------------------------------------------------------------------
c
      return
      end