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Drawing ships: LL9_b1

[NES version, Bank 7]

Name: LL9_b1 [Show more] Type: Subroutine Category: Drawing ships Summary: Call the LL9 routine in ROM bank 1 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: * DrawShipInBitplane calls LL9_b1 * Main flight loop (Part 12 of 16) calls LL9_b1
.LL9_b1 LDA currentBank ; If ROM bank 1 is already paged into memory, jump to CMP #1 ; bank3 BEQ bank3 PHA ; Otherwise store the current bank number on the stack LDA #1 ; Page ROM bank 1 into memory at $8000 JSR SetBank JSR LL9 ; Call LL9, 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 .bank3 JMP LL9 ; Call LL9, which is already paged into memory, and ; return from the subroutine using a tail call