Skip to navigation

⌂ ∞ Elite on the BBC Micro and NES

PPU: SendSpaceViewToPPU

[NES version, Bank 0]

       Name: SendSpaceViewToPPU                                      [Show more]
       Type: Subroutine
   Category: PPU
    Summary: Set a new space view, clear the screen, copy the nametable buffers
             and configure the PPU for the new view
  Deep dive: Views and view types in NES Elite

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * LOOK1 calls SendSpaceViewToPPU




 Arguments:

   X                    The space view to set:

                          * 0 = front

                          * 1 = rear

                          * 2 = left

                          * 3 = right

                          * 4 = generating a new space view



.SendSpaceViewToPPU

 LDA #72                ; Set the screen height variables for a screen height of
 JSR SetScreenHeight    ; 144 (i.e. 2 * 72)

 STX VIEW               ; Set the current space view to X

 LDA #$00               ; Clear the screen and set the view type in QQ11 to $00
 JSR TT66               ; (Space view with no fonts loaded)

 JSR CopyNameBuffer0To1 ; Copy the contents of nametable buffer 0 to nametable
                        ; buffer

 JSR SendViewToPPU_b3   ; Configure the PPU for the view type in QQ11

 JMP ResetStardust      ; Hide the sprites for the stardust and return from the
                        ; subroutine using a tail call