|
|
@ -16,12 +16,7 @@ |
|
|
|
|
|
|
|
Start: |
|
|
|
InitSNES ; Initialize SNES. |
|
|
|
|
|
|
|
; Set the background color. |
|
|
|
; $2121 is the color palette selection register [CGADD]. |
|
|
|
; Storing 0 because that's the SNES background color. |
|
|
|
stz $2121 |
|
|
|
|
|
|
|
|
|
|
|
; Turn on the screen. |
|
|
|
; $2100: Screen display register [INIDISP] |
|
|
|
; |
|
|
@ -148,7 +143,7 @@ JoypadY: |
|
|
|
bne JoypadDone ; Button not pressed. |
|
|
|
lda $21 |
|
|
|
cmp #0 |
|
|
|
beq JoypadDone |
|
|
|
beq JoypadDone ; Value saturated. |
|
|
|
dec $21 |
|
|
|
|
|
|
|
JoypadDone: |
|
|
@ -174,7 +169,7 @@ SetBackgroundColor: |
|
|
|
; $20 $21 $22 are (R, G, B), each ranging from [0-31]. |
|
|
|
; The palette color format is 15-bit: [0bbbbbgg][gggrrrrr] |
|
|
|
|
|
|
|
; Compute and store the low-order byte. |
|
|
|
; Compute and the low-order byte and store it in CGDATA. |
|
|
|
lda $21 ; Green. |
|
|
|
.rept 5 |
|
|
|
asl |
|
|
@ -182,7 +177,7 @@ SetBackgroundColor: |
|
|
|
ora $20 ; Red. |
|
|
|
sta $2122 |
|
|
|
|
|
|
|
; Compute and store the high-order byte. |
|
|
|
; Compute the high-order byte and store it in CGDATA. |
|
|
|
lda $22 ; Blue. |
|
|
|
.rept 2 |
|
|
|
asl |
|
|
@ -194,6 +189,11 @@ SetBackgroundColor: |
|
|
|
.endr |
|
|
|
ora $00 |
|
|
|
sta $2122 |
|
|
|
|
|
|
|
; Set the background color. |
|
|
|
; $2121 is the color palette selection register [CGADD]. |
|
|
|
; Entry 0 corresponds to the SNES background color. |
|
|
|
stz $2121 |
|
|
|
rts |
|
|
|
|
|
|
|
|
|
|
|