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Drawing the screen: SetupViewInNMI_b3

[NES version, Bank 7]

Name: SetupViewInNMI_b3 [Show more] Type: Subroutine Category: Drawing the screen Summary: Call the SetupViewInNMI 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: * SetSpaceViewInNMI calls SetupViewInNMI_b3
.SetupViewInNMI_b3 LDA #%11000000 ; Set A to the bitplane flags to set for the drawing ; bitplane in the call to SetupViewInNMI below: ; ; * Bit 2 clear = send tiles up to configured numbers ; * Bit 3 clear = don't clear buffers after sending ; * Bit 4 clear = we've not started sending data yet ; * Bit 5 clear = we have not yet sent all the data ; * Bit 6 set = send both pattern and nametable data ; * Bit 7 set = send data to the PPU ; ; Bits 0 and 1 are ignored and are always clear STA storeA ; Store the value of A so we can retrieve it below LDA currentBank ; If ROM bank 3 is already paged into memory, jump to CMP #3 ; bank18 BEQ bank18 PHA ; Otherwise store the current bank number on the stack LDA #3 ; Page ROM bank 3 into memory at $8000 JSR SetBank LDA storeA ; Restore the value of A that we stored above JSR SetupViewInNMI ; Call SetupViewInNMI, 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 .bank18 LDA storeA ; Restore the value of A that we stored above JMP SetupViewInNMI ; Call SetupViewInNMI, which is already paged into ; memory, and return from the subroutine using a tail ; call