nolist VRAMLINES_C000 equ &4200 SINEDATA equ &8000 AMP equ 14 BASE equ 128 org &4000 run $ nframe: xor a call &bc0e di ld h,BASE ld l,0 ; Optional, works well with other values ld iyh,BASE*2 and 255 ; For symmetry ld de,AMP*&3f + AMP/2 ld bc,-AMP ld ix,SINEDATA + &80 singen ld a,iyh sub h ld (ix+0),a ld (ix-&80),h add hl,de ex de,hl add hl,bc ex de,hl inc ixl jr nz,singen ; -- Done -- ld de,&C008+640: ld hl,VRAMLINES_C000 ;call generate_vram80 ld c,80 ld a,25 rows25: ex af,af' push de ld b,8 lines8: ld (hl),e:inc hl:ld (hl),d:inc hl ld a,d:add 8:ld d,a dec b jr nz,lines8 pop de ex de,hl:add hl,bc:ex de,hl ex af,af' dec a jr nz,rows25 loop: ld hl,nframe inc (hl) ld b,(hl) ld hl,VRAMLINES_C000 ld ixl,96 pixY: ld e,(hl):inc hl:ld d,(hl):inc hl push hl ld c,64 pixX: ld h,SINEDATA/256 ld a,ixl:ld l,a:ld a,(hl) ld l,c:ld l,(hl):add l:add b ld l,a srl l ld a,b cp 128 jr c,you srl l you: ld a,l and a,15 ld (de),a:inc de dec c jr nz,pixX pop hl dec ixl jr nz,pixY jr loop list aend: nolist