.macro color lda v2001 and #%11111110 sta v2001 sta $2001 .endmacro .macro mono lda v2001 ora #%00000001 sta v2001 sta $2001 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Load 16-bit pointer (for indirect addressing) ; (macro: pointer target,zeropage) ;--------------------------------------------------------- .macro pointer addr,addr2 lda #addr sta addr2+1 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; 16-bit compare ; (macro: cmp16 addr1,addr2,branch_label (if not equal) ;--------------------------------------------------------- .macro cmp16 addr,addr2,branch lda addr cmp addr2 bne branch lda addr+1 cmp addr2+1 bne branch .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; 16-bit increment (macro: inc16 address) ;--------------------------------------------------------- .macro inc16 addr .local label inc addr bne label inc addr+1 label: .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; 16-bit decrement (macro: dec16 address) ; (this is slower than an increment) ;--------------------------------------------------------- .macro dec16 addr lda addr bne :+ dec addr+1 : dec addr .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Enable BG and OBJ (macro: screen_on) ;--------------------------------------------------------- .macro screen_on lda v2001 ora #%00011000 sta v2001 sta $2001 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Disable BG and OBJ (macro: screen_off) ;--------------------------------------------------------- .macro screen_off lda v2001 and #%11100111 sta v2001 sta $2001 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Wait until vblank NMI has finished (macro: vblank) ; NMIs must be enabled, or this will lock up ;--------------------------------------------------------- .macro vblank : lda vb_hit beq :- lda #0 sta vb_hit .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Enable NMI ;--------------------------------------------------------- .macro nmi_enable lda v2000 ora #$80 sta v2000 sta $2000 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Disable NMI ;--------------------------------------------------------- .macro nmi_disable lda v2000 and #$7F sta v2000 sta $2000 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Enable Clipping for BG and OBJs (8 pixels of the left border) ;--------------------------------------------------------- .macro clipping_enable lda v2001 and #%11111001 sta v2001 sta $2001 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Disable Clipping for BG and OBJs (8 pixels of the left border) ;--------------------------------------------------------- .macro clipping_disable lda v2001 ora #%00000110 sta v2001 sta $2001 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Set Horizontal VRAM writing (auto-inc by 1) ;--------------------------------------------------------- .macro vram_h lda v2000 and #%11111011 sta v2000 sta $2000 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Set Vertical VRAM writing (auto-inc by 32) ;--------------------------------------------------------- .macro vram_v lda v2000 ora #%00000100 sta v2000 sta $2000 .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Check Controller ; (macro: controller button,branch,(optional)branch ;--------------------------------------------------------- .macro controller button,not_pressed,button_held .ifblank button_held lda joy1 and #button beq not_pressed .endif .ifnblank button_held lda joy1 and #button beq not_pressed and joy1old bne button_held .endif .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Initialize NES (and clear memory) ;--------------------------------------------------------- .macro nes_init sei cld ldx #0 stx $2000 stx $2001 stx $4015 @wait: lda $2002 bpl @wait @wait2: lda $2002 bpl @wait2 dex txs inx txa clear_ram: sta $00, x sta $200, x sta $300, x sta $400, x sta $500, x sta $600, x sta $700, x inx bne clear_ram .endmacro ;--------------------------------------------------------- ;--------------------------------------------------------- ; Setup a sprite (object) ;--------------------------------------------------------- .macro sprite number,tile,Ycoord,Xcoord,attribute lda #Ycoord sta sprites+number*4 lda #tile sta sprites+1+number*4 .ifnblank attribute lda #attribute sta sprites+2+number*4 .endif lda #Xcoord sta sprites+3+number*4 .endmacro ;---------------------------------------------------------