diff options
| author | Alexey 'Cluster' Avdyukhin <clusterrr@clusterrr.com> | 2020-12-28 13:21:03 +0300 |
|---|---|---|
| committer | Alexey 'Cluster' Avdyukhin <clusterrr@clusterrr.com> | 2020-12-28 13:21:03 +0300 |
| commit | 4dcfbe0894229b229df823069eb2805cd4d73346 (patch) | |
| tree | 3addc77530ab3f4365e56da8bd1c9d8b4d52a4e9 /video.asm | |
| parent | 5e82db207436e6fd472c742a4f4b8827cdc7105a (diff) | |
Comments and minor fixes
Diffstat (limited to 'video.asm')
| -rw-r--r-- | video.asm | 28 |
1 files changed, 9 insertions, 19 deletions
@@ -31,7 +31,7 @@ waitblank: bit $2002 ; reset vblank bit .loop: lda $2002 ; load A with value at location $2002 - bpl .loop ; if bit 7 is not set (not VBlank) keep checking + bpl .loop ; if bit 7 is not set (not VBlank) keep checking ; scrolling jsr move_scrolling @@ -64,8 +64,9 @@ waitblank_simple: rts scroll_fix: - ; scrollong reset - bit $2002 + ; scrolling reset + bit $2002 + ; X coordinate always 0 lda #0 sta $2005 lda <SCROLL_LINES_MODULO @@ -78,7 +79,8 @@ scroll_fix: .first_screen: ldy #%00001000 ; first nametable .really: - sty $2000 + sty $2000 ; set base nametable + ; calculating Y coordinate asl A asl A asl A @@ -134,7 +136,7 @@ scroll_line_up: sbc #0 sta <SCROLL_LINES+1 dec <SCROLL_LINES_MODULO - lda <SCROLL_LINES_MODULO + ;lda <SCROLL_LINES_MODULO bpl .modulo_ok lda #LINES_PER_SCREEN sta <SCROLL_LINES_MODULO @@ -148,7 +150,7 @@ scroll_line_up: sbc #0 sta <LAST_LINE_GAME+1 dec <LAST_LINE_MODULO - lda <LAST_LINE_MODULO + ;lda <LAST_LINE_MODULO bpl .modulo_ok2 lda #LINES_PER_SCREEN sta <LAST_LINE_MODULO @@ -181,23 +183,11 @@ load_base_pal: inx cpx #32 bne .loop - ; letters colors -; lda #$3F -; sta $2006 -; lda #$0D -; sta $2006 -; ldx #17 -;.loop2: -; lda tilepal, x -; sta $2007 -; inx -; cpx #20 -; bne .loop2 rts ; loading empty black palette into $3F00 of PPU load_black: - ; waiting for vbland + ; waiting for vblank ; need even if rendering is disabled ; to prevent lines on black screen jsr waitblank_simple |