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⌂ ∞ Elite on the BBC Micro and NES

Drawing the screen: SetupSpaceView

[NES version, Bank 0]

       Name: SetupSpaceView                                          [Show more]
       Type: Subroutine
   Category: Drawing the screen
    Summary: Set up the NMI variables for the space view

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




.SetupSpaceView

 LDA #$FF               ; Set showIconBarPointer = $FF to indicate that we
 STA showIconBarPointer ; should show the icon bar pointer

 LDA #$2C               ; Set the visible colour to cyan ($2C)
 STA visibleColour

 LDA firstFreePattern   ; Tell the NMI handler to send pattern entries from the
 STA firstPattern       ; first free pattern onwards, so we don't waste time
                        ; resending the static patterns we have already sent

 LDA #80                ; Tell the NMI handler to only clear nametable entries
 STA maxNameTileToClear ; up to tile 80 * 8 = 640 (i.e. up to the end of tile
                        ; row 19)

 LDX #8                 ; Tell the NMI handler to send nametable entries from
 STX firstNameTile      ; tile 8 * 8 = 64 onwards (i.e. from the start of tile
                        ; row 2)

 LDA #116               ; Tell the NMI handler to send nametable entries up to
 STA lastNameTile       ; tile 116 * 8 = 800 (i.e. up to the end of tile row 28)
                        ; in bitplane 0

 RTS                    ; Return from the subroutine