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⌂ ∞ Elite on the BBC Micro and NES

Maths (Arithmetic): MULT12

[NES version, Bank 7]

       Name: MULT12                                                  [Show more]
       Type: Subroutine
   Category: Maths (Arithmetic)
    Summary: Calculate (S R) = Q * A

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * TAS3 calls MULT12
             * TAS4 calls MULT12
             * TIDY calls MULT12
             * TIS3 calls MULT12




 Calculate:

   (S R) = Q * A



.MULT12

 JSR MULT1              ; Set (A P) = Q * A

 STA S                  ; Set (S P) = (A P)
                        ;           = Q * A

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

 LDA P                  ; Set (S R) = (S P)
 STA R                  ;           = Q * A

 RTS                    ; Return from the subroutine