git.y1.nz

commit 06dee0fbad8e615a548db28a2dc7028a3f538eeb
parent 112036a6d9aee53b858794a5f43ee432dc72b648
Author: toxa <untoxa@mail.ru>
Date:   Wed, 28 Oct 2020 00:56:03 +0300

wait_int_handler fixed; set_*_data function sources cleanup

Diffstat:
M
gbdk-lib/libc/gb/crt0.s
6
++++--
M
gbdk-lib/libc/gb/lcd.s
3
++-
M
gbdk-lib/libc/gb/nowait.s
16
----------------
M
gbdk-lib/libc/gb/set_1bit_data.s
9
++++-----
M
gbdk-lib/libc/gb/set_data.s
96
++++++++++++++++++-------------------------------------------------------------

5 files changed, 32 insertions(+), 98 deletions(-)
diff --git a/gbdk-lib/libc/gb/crt0.s b/gbdk-lib/libc/gb/crt0.s
@@ -64,7 +64,7 @@
 1$:
 	LD	A,(HL+)
 	OR	(HL)
-	JR	Z,2$
+	JR	Z,.int_tail
 	PUSH	HL
 	LD	A,(HL-)
 	LD	L,(HL)
@@ -73,7 +73,9 @@
 	POP	HL
 	INC	HL
 	JR	1$
-2$:
+_wait_int_handler::    
+	ADD	SP,#4
+.int_tail:
 	POP	DE
 	POP	BC
 	POP	HL
diff --git a/gbdk-lib/libc/gb/lcd.s b/gbdk-lib/libc/gb/lcd.s
@@ -26,7 +26,8 @@
 	LD	A,(HL+)
 	LD      H,(HL)
 	LD	L,A
-				; don't need to check the first one: if 0, then call an empty handler
+	OR	H
+	JR 	Z, 1$
 	RST     0x20		; .call_hl
 	LD	HL, #.int_0x48 + 2
 	LD	A,(HL+)
diff --git a/gbdk-lib/libc/gb/nowait.s b/gbdk-lib/libc/gb/nowait.s
@@ -8,19 +8,3 @@ _nowait_int_handler::
 	POP	HL 
 	POP	AF
 	RETI
-
-_wait_int_handler::    
-	ADD	SP,#4
-	POP	DE 
-	POP	BC
-	POP	HL 
-1$:
-	LDH	A,(#_STAT_REG)
-	AND	#0X02
-	JR	Z,1$
-2$:
-	LDH	A, (#_STAT_REG)
-	AND	#0X02
-	JR	NZ, 2$
-	POP	AF
-	RETI
diff --git a/gbdk-lib/libc/gb/set_1bit_data.s b/gbdk-lib/libc/gb/set_1bit_data.s
@@ -38,17 +38,16 @@ _set_sprite_1bit_data::
 	ld a, e
 	and #0xF0 ; Get low bits only
 	ld e, a
-	
 1$:
 	; Wrap from past $97FF to $8800 onwards
 	; This can be reduced to "bit 4 must be clear if bit 3 is set"
 	bit 3, d
 	jr z, 2$
 	res 4, d
-2$:	
-	.rept 3		; Repeat this 4 more times to copy 16 bytes...
+2$:
+	.rept 3		; Repeat this 3 times to copy 12 bytes...
 		WAIT_STAT
-		; We have 16 cycles free to access VRAM, during which we can copy 3 bytes
+		; We have 16 cycles free to access VRAM, during which we can expand 2 bytes into 4 bytes
 		ld a, (hl+)
 		ld (de), a
 		inc e ; inc de
@@ -61,7 +60,7 @@ _set_sprite_1bit_data::
 		inc e ; inc de
 	.endm
 	WAIT_STAT
-	; We have 16 cycles free to access VRAM, during which we can copy 3 bytes
+	; We have 16 cycles free to access VRAM, during which we can expand 2 bytes into 4 byte
 	ld a, (hl+)
 	ld (de), a
 	inc e ; inc de
diff --git a/gbdk-lib/libc/gb/set_data.s b/gbdk-lib/libc/gb/set_data.s
@@ -5,6 +5,12 @@
 	;; BANKED:	checked
 	.area	_BASE
 
+.macro WAIT_STAT ?lbl
+lbl:	ldh a, (.STAT)
+	and #2 ; Check if in LCD modes 0 or 1
+	jr nz, lbl
+.endm
+
 _set_bkg_data::
 _set_win_data::
 	ld d, #0x90
@@ -33,90 +39,32 @@ _set_sprite_data::
 	ld a, e
 	and #0xF0 ; Get low bits only
 	ld e, a
-	
-copy_tile$:
+2$:
 	; Wrap from past $97FF to $8800 onwards
 	; This can be reduced to "bit 4 must be clear if bit 3 is set"
 	bit 3, d
 	jr z, 1$
 	res 4, d
 1$:
-	ldh a, (.STAT)
-	and #2 ; Check if in LCD modes 0 or 1
-	jr nz, 1$
-	; We have 16 cycles free to access VRAM, during which we can copy 3 bytes
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	; Repeat this 4 more times to copy 15 of the 16 bytes...
-2$:
-	ldh a, (.STAT)
-	and #2
-	jr nz, 2$
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-3$:
-	ldh a, (.STAT)
-	and #2
-	jr nz, 3$
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-4$:
-	ldh a, (.STAT)
-	and #2
-	jr nz, 4$
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-5$:
-	ldh a, (.STAT)
-	and #2
-	jr nz, 5$
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	ld a, (hl+)
-	ld (de), a
-	inc e ; inc de
-	; Now, copy the final byte, wherein we will increment `de` in full
-6$:
-	ldh a, (.STAT)
-	and #2
-	jr nz, 6$
+	.rept 5
+		WAIT_STAT
+		ld a, (hl+)
+		ld (de), a
+		inc e ; inc de
+		ld a, (hl+)
+		ld (de), a
+		inc e ; inc de
+		ld a, (hl+)
+		ld (de), a
+		inc e ; inc de
+	.endm
+	WAIT_STAT
 	ld a, (hl+)
 	ld (de), a
 	inc de ; This actually can overflow into the high byte
+
 	dec c
-	jr nz, copy_tile$
+	jr nz, 2$
 	
 	pop bc
 	ret
 

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