;------------------------------------------------------------------------ ;- Written by: Neviksti ;- If you use my code, please share your creations with me ;- as I am always curious :) ;------------------------------------------------------------------------ .BANK 0 SLOT 0 .ORG HEADER_OFF .SECTION "QuickCodeSection" SEMIFREE VBlank: pha ; phx ; phy ; make sure to store all registers phb ; before you run your IRQ routine php ; and pull them back after you're done phk ; so when it returns it will not have screwed plb ; up anything! sep #$20 ; mem/A = 8 bit, X/Y = 16 bit rep #$10 jump jDoScrolling ;;change sprite graphics here lda cursorX sta SpriteBuf1 lda cursorY sec sbc #$10 ; clc ; adc #$08 sta SpriteBuf1+1 ;*********transfer sprite data stz $2102 ; set OAM address to 0 stz $2103 LDY #$0400 STY $4300 ; CPU -> PPU, auto increment, write 1 reg, $2104 (OAM data write) LDY #SpriteBuf1 STY $4302 ; source offset LDY #$0220 STY $4305 ; number of bytes to transfer LDA #$00 STA $4304 ; bank address = $7F (work RAM) LDA #$01 STA $420B ;start DMA transfer channel 2 ;*********transfer BG3 data LDA #$00 STA $2115 ;set up VRAM write to write only the lower byte LDX #$0400 STX $2116 ;set VRAM address to BG3 tile map LDY #$1800 STY $4300 ; CPU -> PPU, auto increment, write 1 reg, $2118 (Lowbyte of VRAM write) LDY #TextBuffer STY $4302 ; source offset LDY #$0400 STY $4305 ; number of bytes to transfer LDA #$00 STA $4304 ; bank address = $7F (work RAM) LDA #$01 STA $420B ;start DMA transfer channel 2 ;update the joypad data JSR GetInput lda scrollY sta $2112 ;lda scrollX+1 ;Scroll BG3 vertical stz $2112 lda $4210 ;clear NMI Flag REP #$30 ;A/Mem=16bits, X/Y=16bits inc FrameNum plp ; pull original registers back! plb ; ply ; plx ; pla ; RTI ;============================================================================ QuickSetup: php rep #$10 ;A/mem = 8bit, X/Y=16bit sep #$20 ;Load palette to make our pictures look correct LoadPalette BG_Palette ;Load Tile and Character data to VRAM LoadBlockToVRAM ASCIITiles, $0000, $0800 ;128 tiles * (2bit color = 2 planes) --> 2048 bytes LoadBlockToVRAM SpriteTiles, $6000, $2000 ;16 32x32 tiles * (4bit color = 4 planes) --> 8192 bytes ;Set the priority bit of all the BG3 tiles LDA #$80 STA $2115 ;set up the VRAM so we can write just to the high byte LDX #$0400 STX $2116 LDX #$0400 ;32x32 tiles = 1024 LDA #$20 __next_tile: STA $2119 DEX BNE __next_tile ;lda #$A3 ;Sprites 32x32 or 64x64, character data at $6000 (word address) lda #%01100011 ;16x16 sprites sta $2101 lda #$01 ;Set video mode 1, 8x8 tiles (16 color BG1 + BG2, 4 color BG3) sta $2105 lda #$08 ;Set BG1's Tile Map VRAM offset to $0800 (word address) sta $2107 ; and the Tile Map size to 32 tiles x 32 tiles lda #$0C ;Set BG2's Tile Map VRAM offset to $0C00 (word address) sta $2108 ; and the Tile Map size to 32 tiles x 32 tiles lda #$04 ;Set BG3's Tile Map VRAM offset to $0400 (word address) sta $2109 ; and the Tile Map size to 32 tiles x 32 tiles lda #$41 ;Set BG1's Character VRAM offset to $1000 (word address) sta $210B ;Set BG2's Character VRAM offset to $4000 (word address) lda #$00 ;Set BG3's Character VRAM offset to $0000 (word address) sta $210C ; lda #%00010100 ;Turn on BG1 and BG2 and BG3 and sprites sta $212C sta $212E lda #$FF ;Scroll BG3 down 1 pixel sta $2112 ; lda scrollX+1 stz $2112 stz $2111 ;bg3 horiz scroll stz $2111 lda #$0F ;Turn on screen, full brightness sta $2100 plp rts DoScrolling: CheckCursor: ;check cursor counter, no scroll if counter=0 lda cursorYCounter cmp #$00 beq CursorDone dec cursorYCounter ;scroll = scroll + scrollUp - scrollDown CursorScroll: lda cursorY sec sbc cursorYUp clc adc cursorYDown sta cursorY CursorDone: CheckYScroll: ;check scroll counter, no scroll if counter=0 lda scrollYCounter beq DoYScrollDone dec scrollYCounter ;scroll = scroll - scrollUp + scrollDown DoYScroll: lda scrollY sec sbc scrollYUp clc adc scrollYDown sta scrollY ; cmp #$F0 ; 240 ; bcc DoYScrollDone ; scrollY < 240, no underflow/overflow ;DoYScrollOverflow: ; cmp #$F8 ; 248 ; bcs DoYScrollUnderflow ; scrollY > 248, no overflow ; sec ; sbc #$F0 ; scroll = scroll - 240 ; sta scrollY ; jmp DoYScrollDone ;DoYScrollUnderflow: ; lda scrollY ; sec ; sbc #$10 ; sta scrollY DoYScrollDone: rts ScrollUp: sec lda selectedEntry sbc #$01 sta selectedEntry lda selectedEntry+1 ;go to prev entry sbc #$00 sta selectedEntry+1 lda selectedEntry cmp #$FF bne ScrollUpCheckTop lda selectedEntry+1 cmp #$FF bne ScrollUpCheckTop ;check if selectedEntry = FFFF (underflow) lda filesInDir sta selectedEntry lda filesInDir+1 sta selectedEntry+1 ;underflow, reset selectedEntry = filesInDir-1 sec lda selectedEntry sbc #$01 sta selectedEntry lda selectedEntry+1 sbc #$00 sta selectedEntry+1 lda filesInDir+1 cmp #$00 bne ScrollUpCheckTop lda filesInDir cmp #$1d bcs ScrollUpCheckTop ; check if filesInDir > 28 lda filesInDir asl a asl a asl a ;multiply by 8 for sprite height clc adc #$08 sta cursorY ; put cursor at bottom of list jmp ScrollUpCheckMiddle ScrollUpCheckTop: lda cursorY cmp #$08 bne ScrollUpCheckMiddle ;check if cursor at top lda speedCounter sta scrollYCounter ;cursor at top, scroll background, leave cursor lda speedScroll sta scrollYUp lda #$00 sta scrollYDown lda insertTop sta temp jump jPrintClearLine lda temp asl a asl a asl a asl a asl a sta Cursor lda temp lsr a lsr a lsr a sta Cursor+1 jump jDirPrintEntry lda insertBottom sec sbc #$01 and #%00011111 sta insertBottom lda insertTop sec sbc #$01 and #%00011111 sta insertTop jmp ScrollUpDone ScrollUpCheckMiddle: lda speedCounter sta cursorYCounter lda speedScroll sta cursorYUp lda #$00 sta cursorYDown ScrollUpDone: rts ScrollDown: clc lda selectedEntry adc #$01 sta selectedEntry lda selectedEntry+1 ;go to next entry adc #$00 sta selectedEntry+1 lda selectedEntry cmp filesInDir bne ScrollDownCheckBottom lda selectedEntry+1 cmp filesInDir+1 bne ScrollDownCheckBottom ;check if selectedEntry = filesInDir lda #$00 sta selectedEntry sta selectedEntry+1 ;overflow, reset to 0 lda filesInDir+1 cmp #$00 bne ScrollDownCheckBottom lda filesInDir cmp #$1d bcs ScrollDownCheckBottom ; check if filesInDir > 28 lda #$00 sta cursorY ; put cursor at top of screen jmp ScrollDownCheckMiddle ScrollDownCheckBottom: lda cursorY cmp #$E0 ;= pixel 224 bne ScrollDownCheckMiddle ; check if cursor at bottom lda speedCounter ;cursor at bottom, move background, leave cursor sta scrollYCounter ;set scrollYCounter (8 or 4) lda speedScroll sta scrollYDown ;set scrollYDown to speed (1 or 2) lda #$00 sta scrollYUp ScrollDownCheckBottomDone: lda insertBottom sta temp jump jPrintClearLine lda temp asl a asl a asl a asl a asl a sta Cursor lda temp lsr a lsr a lsr a sta Cursor+1 jump jDirPrintEntry lda insertBottom clc adc #$01 and #%00011111 sta insertBottom lda insertTop clc adc #$01 and #%00011111 sta insertTop jmp ScrollDownDone ScrollDownCheckMiddle: lda speedCounter sta cursorYCounter lda speedScroll sta cursorYDown lda #$00 sta cursorYUp ScrollDownDone: rts .ENDS ;========================================================================================== .BANK 1 SLOT 0 .ORG 0 .SECTION "CharacterData" BG_Palette: ;.INCBIN ".\\Pictures\\ascii.clr"; ;.REPT 128 ;.DW 0 ;.ENDR .INCBIN ".\\Pictures\\mymap2.clr" .INCBIN ".\\Pictures\\dwarf2.clr" ASCIITiles: .INCBIN ".\\Pictures\\ascii.smc" SpriteTiles: .INCBIN ".\\Pictures\\dwarf.smc" .ENDS ;==========================================================================================