byte ds_graphics @ $C050
byte ds_text     @ $C051
byte ds_full     @ $C052
byte ds_split    @ $C053
byte ds_page1    @ $C054
byte ds_page2    @ $C055
byte ds_lores    @ $C056
byte ds_hires    @ $C057

define main routine
  inputs a
  outputs ds_lores, ds_page1, ds_split, ds_graphics
  trashes a, z, n
{
    ld a, 0
    st a, ds_lores
    st a, ds_page1
    st a, ds_split
    st a, ds_graphics
}