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⌂ ∞ ▽ Elite on the 6502

Icon bar: UpdateIconBar_b3

[NES version, Bank 7]

       Name: UpdateIconBar_b3                                        [Show more]
       Type: Subroutine
   Category: Icon bar
    Summary: Call the UpdateIconBar routine in ROM bank 3
  Deep dive: Splitting NES Elite across multiple ROM banks

    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * ABORT2 calls UpdateIconBar_b3
             * DrawScrollText calls UpdateIconBar_b3
             * ESCAPE calls UpdateIconBar_b3
             * Ghy calls UpdateIconBar_b3
             * hyp1 calls UpdateIconBar_b3
             * KS4 calls UpdateIconBar_b3
             * Main flight loop (Part 3 of 16) calls UpdateIconBar_b3
             * Main flight loop (Part 13 of 16) calls UpdateIconBar_b3
             * Main game loop (Part 5 of 6) calls UpdateIconBar_b3
             * MJP calls UpdateIconBar_b3
             * MoveInMiddleColumn calls UpdateIconBar_b3
             * NWSPS calls UpdateIconBar_b3
             * OUCH calls UpdateIconBar_b3
             * PauseGame calls UpdateIconBar_b3
             * PlayDemo calls UpdateIconBar_b3
             * SetSelectionFlags calls UpdateIconBar_b3
             * TT16 calls UpdateIconBar_b3
             * wW calls UpdateIconBar_b3




.UpdateIconBar_b3

 LDA currentBank        ; If ROM bank 3 is already paged into memory, jump to
 CMP #3                 ; bank20
 BEQ bank20

 PHA                    ; Otherwise store the current bank number on the stack

 LDA #3                 ; Page ROM bank 3 into memory at $8000
 JSR SetBank

 JSR UpdateIconBar      ; Call UpdateIconBar, now that it is paged into memory

 JMP ResetBank          ; Fetch the previous ROM bank number from the stack and
                        ; page that bank back into memory at $8000, returning
                        ; from the subroutine using a tail call

.bank20

 JMP UpdateIconBar      ; Call UpdateIconBar, which is already paged into
                        ; memory, and return from the subroutine using a tail
                        ; call