1 files changed, 51 insertions, 0 deletions
diff --git a/engine/joypad.asm b/engine/joypad.asm
new file mode 100644
index 00000000..d2ad1c31
--- /dev/null
+++ b/engine/joypad.asm
@@ -0,0 +1,51 @@
+_Joypad::
+	ld a, [hJoyInput]
+	cp A_BUTTON + B_BUTTON + SELECT + START ; soft reset
+	jp z, TrySoftReset
+	ld b, a
+	ld a, [hJoyHeldLast]
+	ld e, a
+	xor b
+	ld d, a
+	and e
+	ld [hJoyReleased], a
+	ld a, d
+	and b
+	ld [hJoyPressed], a
+	ld a, b
+	ld [hJoyHeldLast], a
+	ld a, [wd730]
+	bit 5, a
+	jr nz, DiscardButtonPresses
+	ld a, [hJoyHeldLast]
+	ld [hJoyHeld], a
+	ld a, [wJoyIgnore]
+	and a
+	ret z
+	cpl
+	ld b, a
+	ld a, [hJoyHeld]
+	and b
+	ld [hJoyHeld], a
+	ld a, [hJoyPressed]
+	and b
+	ld [hJoyPressed], a
+	ret
+
+DiscardButtonPresses:
+	xor a
+	ld [hJoyHeld], a
+	ld [hJoyPressed], a
+	ld [hJoyReleased], a
+	ret
+
+TrySoftReset:
+	call DelayFrame
+	; reset joypad (to make sure the
+	; player is really trying to reset)
+	ld a, $30
+	ld [rJOYP], a
+	ld hl, hSoftReset
+	dec [hl]
+	jp z, SoftReset
+	jp Joypad