.equ cm_set_page  = 0b10110000
                      .equ cm_set_col1  = 0b00010000
                      .equ cm_set_col2  = 0b00000000


;----------------------------------------------------------------------------------------
;                     in : r18 Spaltennummer


set_column:           push r16
                      push r17
                      push r18

                      set_command

                      mov r16,r18
                      mov r17,r18
                      swap r16
                      andi r16,$0F
                      andi r17,$0F

                      ldi r18,cm_set_col1
                      or r18,r16
                      rcall out_spi
                      ldi r18,cm_set_col2
                      or r18,r17
                      rcall out_spi

                      pop r18
                      pop r17
                      pop r16
                      ret

;----------------------------------------------------------------------------------------
;                     in : r18 Pagenummer

set_page:             push r16
                      push r18

                      set_command
                      andi r18,pages-1               ; Pages = 8
                      ldi r16,cm_set_page
                      or r18,r16
                      rcall out_spi

                      pop r18
                      pop r16
                      ret