SUBROUTINE ZES_FIX_DST97(dstwords)

c     code to fix the GSLT passthrough DST bits for 1997
c
c     bit 2 = GSLT passthrough of any GFLT event with fixed prescale
c     bit 3 = passthrough at GSLT of selected GFLT bits at max rate
c             
c     !! sbit counts from 1, so these are DST bits 2 and 3, counted from 0!!

      IMPLICIT NONE

      integer dstwords(4)
      logical gsltpassthrough,fltbitpassthrough,slterr
      integer fltpasbits(2),err

      call gsltpasstype(gsltpassthrough,fltbitpassthrough
     &                 ,fltpasbits,slterr,err)
      if (err.ne.0) then
         write(6,*) 'gsltpasstype error: ',err
         goto 999
      endif

      if (gsltpassthrough) then
        call sbit1(dstwords(1),3)
      else
        call sbit0(dstwords(1),3)
      endif
      if (fltbitpassthrough) then
        call sbit1(dstwords(1),4)
      else
        call sbit0(dstwords(1),4)
      endif

 999  continue
      end