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⌂ ∞ Elite on the BBC Micro and NES

Combat demo: RunDemoFlightLoop

[NES version, Bank 0]

       Name: RunDemoFlightLoop                                       [Show more]
       Type: Subroutine
   Category: Combat demo
    Summary: Run a fixed number of iterations of the main flight loop for the
             combat demo
  Deep dive: Splitting the main loop in the NES version
             The NES combat demo

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




 Arguments:

   A                    The number of iterations of the main flight loop to run



.RunDemoFlightLoop

 STA LASCT              ; Store the number of iterations in LASCT so we can
                        ; access it after running the main flight loop

.dlop1

 JSR FlipDrawingPlane   ; Flip the drawing bitplane so we draw into the bitplane
                        ; that isn't visible on-screen

 JSR FlightLoop4To16    ; Display in-flight messages, call parts 4 to 12 of the
                        ; main flight loop for each ship slot, and finish off
                        ; with parts 13 to 16 of the main flight loop

 JSR DrawBitplaneInNMI  ; Configure the NMI to send the drawing bitplane to the
                        ; PPU after drawing the box edges and setting the next
                        ; free tile number

 LDA iconBarChoice      ; Set A to the number of the icon bar button that has
                        ; been chosen from the icon bar (if any)

 JSR CheckForPause      ; If the Start button has been pressed then process the
                        ; pause menu and set the C flag, otherwise clear it

 DEC LASCT              ; Decrement the iteration counter in LASCT

 BNE dlop1              ; Loop back to run the main flight loop again until we
                        ; have run it the required number of times

 RTS                    ; Return from the subroutine