Page Comparison

IN:
     A = EP_NEXT
   BHL = pointer to current File Entry

OUT:
   BHL = pointer to next file entry on File Eprom in slot, or first byte of empty space

   Fc = 0, File Eprom available
        Fz = 1, File Entry marked as deleted
        Fz = 0, File Entry is active.
   Fc = 1,
        A = RC_Onf
        File Eprom was not found in slot, or File Entry not available

Registers changed after return:
   ...CDE../IXIY same
   AFB...HL/.... different