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⌂ ∞ Elite on the BBC Micro and NES

Text: DETOK_b2

[NES version, Bank 7]

       Name: DETOK_b2                                                [Show more]
       Type: Subroutine
   Category: Text
    Summary: Call the DETOK routine in ROM bank 2
  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:
             * BRIEF2 calls DETOK_b2
             * BRIS_b0 calls DETOK_b2
             * BRP calls DETOK_b2
             * ChangeCmdrName calls DETOK_b2
             * ChooseLanguage calls DETOK_b2
             * dockEd calls DETOK_b2
             * HME2 calls DETOK_b2
             * MT17 calls DETOK_b2
             * MT28 calls DETOK_b2
             * STATUS calls DETOK_b2
             * TBRIEF calls DETOK_b2
             * TT210 calls DETOK_b2
             * YESNO calls DETOK_b2




.DETOK_b2

 STA storeA             ; Store the value of A so we can retrieve it below

 LDA currentBank        ; If ROM bank 2 is already paged into memory, jump to
 CMP #2                 ; bank14
 BEQ bank14

 PHA                    ; Otherwise store the current bank number on the stack

 LDA #2                 ; Page ROM bank 2 into memory at $8000
 JSR SetBank

 LDA storeA             ; Restore the value of A that we stored above

 JSR DETOK              ; Call DETOK, 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

.bank14

 LDA storeA             ; Restore the value of A that we stored above

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