Read from joypad

homebrew-tutorial/charset.asm

@@ -18,8 +18,8 @@ charset:
         .byte   %00000000
 
     ; tile 0x01
-        .byte   %11111111 ; row 0, color 0
-        .byte   %00000000 ; row 0, color 1
+        .byte   %11110000 ; row 0, color 0
+        .byte   %11111111 ; row 0, color 1
         .byte   %10000001 ; row 1, color 0
         .byte   %00000000 ; row 1, color 1
         .byte   %10000001 ; row 2, color 0
@@ -35,4 +35,25 @@ charset:
         .byte   %11111111 ; row 7, color 0
         .byte   %00000000 ; row 7, color 1
 
+    ; tile 0x02
+    .byte %00000000
+    .byte %11111111
+    .byte %00000000
+    .byte %11111111
+    .byte %00000000
+    .byte %11111111
+    .byte %00000000
+    .byte %11111111
+
+    .byte %00000000
+    .byte %11111111
+    .byte %00000000
+    .byte %11111111
+    .byte %00000000
+    .byte %11111111
+    .byte %00000000
+    .byte %11111111
+
+
+
 charset_end:

homebrew-tutorial/main.asm

@@ -29,13 +29,13 @@ start:
     lda #$00
     sta CGDATA
 
-    ; Color 2 - blue
+    ; Color 2 - green
     lda #$e0
     sta CGDATA
     lda #$03
     sta CGDATA
 
-    ; Color 3 - green
+    ; Color 3 - blue
     lda #$00
     sta CGDATA
     lda #$7c
@@ -69,7 +69,8 @@ start:
     ldx #(VRAM_BG1)
 @loop:
     stx VMADDL
-    stz VMDATAL
+    lda #$00
+    sta VMDATAL
     stz VMDATAH
     inx
     cpx #(VRAM_BG1 + 32 * 29)
@@ -88,12 +89,28 @@ start:
     lda #%00000001
     sta TM
 
-
-
-
     lda #$0f
     sta INIDISP
 
+    lda #$01
+    sta NMITIMEN
+
+mainloop:
+    lda JOY1H
+    bit #%00000100 ; Down button
+    beq down_not_pressed
+        ; write tile 2 to position (4, 8)
+        TILE_X2= 4
+        TILE_Y2= 8
+        ldx #(VRAM_BG1 + (TILE_Y2* 32) + TILE_X2)
+        stx VMADDL
+        lda #$02
+        sta VMDATAL
+        stz VMDATAH
+    down_not_pressed:
+
+    bra mainloop
+
 busywait:
     bra busywait