The PAUSE2 (Bank 2) subroutine - Elite on the BBC Micro and NES

       Name: PAUSE2                                                  [Show more]
       Type: Subroutine
   Category: Controllers
    Summary: Wait until a key is pressed, ignoring any existing key press
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * JMTB calls PAUSE2


.PAUSE2

 JSR DrawScreenInNMI_b0 ; Configure the NMI handler to draw the screen

.paws1

 JSR SetupPPUForIconBar ; If the PPU has started drawing the icon bar, configure
                        ; the PPU to use nametable 0 and pattern table 0

 LDA controller1A       ; Keep looping back to paws1 until either the A button
 ORA controller1B       ; or the B button has been pressed and then released on
 AND #%11000000         ; controller 1
 CMP #%01000000
 BNE paws1

 RTS                    ; Return from the subroutine

[X]

Subroutine DrawScreenInNMI_b0 (category: Drawing the screen)

Call the DrawScreenInNMI routine in ROM bank 0

[X]

Subroutine SetupPPUForIconBar (category: PPU)

If the PPU has started drawing the icon bar, configure the PPU to use nametable 0 and pattern table 0, while preserving A

[X]

Variable controller1A in workspace WP

A shift register for recording presses of the A button on controller 1

[X]

Variable controller1B in workspace WP

A shift register for recording presses of the B button on controller 1

[X]

Label paws1 is local to this routine

Controllers: PAUSE2

[NES version, Bank 2]