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Elite on the BBC Micro and NES

Combat demo: ShowScrollText_b6

[NES version, Bank 7]

Name: ShowScrollText_b6 [Show more] Type: Subroutine Category: Combat demo Summary: Call the ShowScrollText routine in ROM bank 6 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: * DEATH2 calls ShowScrollText_b6 * Main flight loop (Part 15 of 16) calls ShowScrollText_b6
.ShowScrollText_b6 STA storeA ; Store the value of A so we can retrieve it below LDA currentBank ; If ROM bank 6 is already paged into memory, jump to CMP #6 ; bank13 BEQ bank13 PHA ; Otherwise store the current bank number on the stack LDA #6 ; Page ROM bank 6 into memory at $8000 JSR SetBank LDA storeA ; Restore the value of A that we stored above JSR ShowScrollText ; Call ShowScrollText, 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 .bank13 LDA storeA ; Restore the value of A that we stored above JMP ShowScrollText ; Call ShowScrollText, which is already paged into ; memory, and return from the subroutine using a tail ; call