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-rw-r--r--common/joypad.asm491
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diff --git a/common/joypad.asm b/common/joypad.asm
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+JoypadInt: ; 92e
+; Replaced by Joypad, called from VBlank instead of the useless
+; joypad interrupt.
+
+; This is a placeholder in case the interrupt is somehow enabled.
+ reti
+; 92f
+
+ClearJoypadPublic: ; 92f
+ xor a
+; Pressed this frame (delta)
+ ld [hJoyPressed], a
+; Currently pressed
+ ld [hJoyDown], a
+ ret
+; 935
+
+Joypad: ; 935
+; Read the joypad register and translate it to something more
+; workable for use in-game. There are 8 buttons, so we can use
+; one byte to contain all player input.
+
+; Updates:
+
+; hJoypadReleased: released this frame (delta)
+; hJoypadPressed: pressed this frame (delta)
+; hJoypadDown: currently pressed
+; hJoypadSum: pressed so far
+
+; Any of these three bits can be used to disable input.
+ ld a, [$cfbe]
+ and %11010000
+ ret nz
+
+; If we're saving, input is disabled.
+ ld a, [$c2cd]
+ and a
+ ret nz
+
+; We can only get four inputs at a time.
+; We take d-pad first for no particular reason.
+ ld a, D_PAD
+ ld [rJOYP], a
+; Read twice to give the request time to take.
+ ld a, [rJOYP]
+ ld a, [rJOYP]
+
+; The Joypad register output is in the lo nybble (inversed).
+; We make the hi nybble of our new container d-pad input.
+ cpl
+ and $f
+ swap a
+
+; We'll keep this in b for now.
+ ld b, a
+
+; Buttons make 8 total inputs (A, B, Select, Start).
+; We can fit this into one byte.
+ ld a, BUTTONS
+ ld [rJOYP], a
+; Wait for input to stabilize.
+ ld a, [rJOYP]
+ ld a, [rJOYP]
+ ld a, [rJOYP]
+ ld a, [rJOYP]
+ ld a, [rJOYP]
+ ld a, [rJOYP]
+; Buttons take the lo nybble.
+ cpl
+ and $f
+ or b
+ ld b, a
+
+; Reset the joypad register since we're done with it.
+ ld a, $30
+ ld [rJOYP], a
+
+; To get the delta we xor the last frame's input with the new one.
+ ld a, [hJoypadDown] ; last frame
+ ld e, a
+ xor b
+ ld d, a
+; Released this frame:
+ and e
+ ld [hJoypadReleased], a
+; Pressed this frame:
+ ld a, d
+ and b
+ ld [hJoypadPressed], a
+
+; Add any new presses to the list of collective presses:
+ ld c, a
+ ld a, [hJoypadSum]
+ or c
+ ld [hJoypadSum], a
+
+; Currently pressed:
+ ld a, b
+ ld [hJoypadDown], a
+
+; Now that we have the input, we can do stuff with it.
+
+; For example, soft reset:
+ and A_BUTTON | B_BUTTON | SELECT | START
+ cp A_BUTTON | B_BUTTON | SELECT | START
+ jp z, Reset
+
+ ret
+; 984
+
+
+GetJoypadPublic: ; 984
+; Update mirror joypad input from hJoypadDown (real input)
+
+; hJoyReleased: released this frame (delta)
+; hJoyPressed: pressed this frame (delta)
+; hJoyDown: currently pressed
+
+; bit 0 A
+; 1 B
+; 2 SELECT
+; 3 START
+; 4 RIGHT
+; 5 LEFT
+; 6 UP
+; 7 DOWN
+
+ push af
+ push hl
+ push de
+ push bc
+
+; The player input can be automated using an input stream.
+; See more below.
+ ld a, [InputType]
+ cp a, AUTO_INPUT
+ jr z, .auto
+
+; To get deltas, take this and last frame's input.
+ ld a, [hJoypadDown] ; real input
+ ld b, a
+ ld a, [hJoyDown] ; last frame mirror
+ ld e, a
+
+; Released this frame:
+ xor b
+ ld d, a
+ and e
+ ld [hJoyReleased], a
+
+; Pressed this frame:
+ ld a, d
+ and b
+ ld [hJoyPressed], a
+
+; It looks like the collective presses got commented out here.
+ ld c, a
+
+; Currently pressed:
+ ld a, b
+ ld [hJoyDown], a ; frame input
+
+.quit
+ pop bc
+ pop de
+ pop hl
+ pop af
+ ret
+
+.auto
+; Use a predetermined input stream (used in the catching tutorial).
+
+; Stream format: [input][duration]
+; A value of $ff will immediately end the stream.
+
+; Read from the input stream.
+ ld a, [hROMBank]
+ push af
+ ld a, [AutoInputBank]
+ rst Bankswitch
+
+ ld hl, AutoInputAddress
+ ld a, [hli]
+ ld h, [hl]
+ ld l, a
+
+; We only update when the input duration has expired.
+ ld a, [AutoInputLength]
+ and a
+ jr z, .updateauto
+
+; Until then, don't change anything.
+ dec a
+ ld [AutoInputLength], a
+ pop af
+ rst Bankswitch
+ jr .quit
+
+
+.updateauto
+; An input of $ff will end the stream.
+ ld a, [hli]
+ cp a, $ff
+ jr z, .stopauto
+ ld b, a
+
+; A duration of $ff will end the stream indefinitely.
+ ld a, [hli]
+ ld [AutoInputLength], a
+ cp a, $ff
+ jr nz, .next
+
+; The current input is overwritten.
+ dec hl
+ dec hl
+ ld b, NO_INPUT
+ jr .finishauto
+
+.next
+; On to the next input...
+ ld a, l
+ ld [AutoInputAddress], a
+ ld a, h
+ ld [AutoInputAddress+1], a
+ jr .finishauto
+
+.stopauto
+ call StopAutoInput
+ ld b, NO_INPUT
+
+.finishauto
+ pop af
+ rst Bankswitch
+ ld a, b
+ ld [hJoyPressed], a ; pressed
+ ld [hJoyDown], a ; input
+ jr .quit
+; 9ee
+
+
+StartAutoInput: ; 9ee
+; Start reading automated input stream at a:hl.
+
+ ld [AutoInputBank], a
+ ld a, l
+ ld [AutoInputAddress], a
+ ld a, h
+ ld [AutoInputAddress+1], a
+; Start reading the stream immediately.
+ xor a
+ ld [AutoInputLength], a
+; Reset input mirrors.
+ xor a
+ ld [hJoyPressed], a ; pressed this frame
+ ld [hJoyReleased], a ; released this frame
+ ld [hJoyDown], a ; currently pressed
+
+ ld a, AUTO_INPUT
+ ld [InputType], a
+ ret
+; a0a
+
+
+StopAutoInput: ; a0a
+; Clear variables related to automated input.
+ xor a
+ ld [AutoInputBank], a
+ ld [AutoInputAddress], a
+ ld [AutoInputAddress+1], a
+ ld [AutoInputLength], a
+; Back to normal input.
+ ld [InputType], a
+ ret
+; a1b
+
+
+Functiona1b: ; a1b
+
+ call DelayFrame
+
+ push bc
+ call Functiona57
+ pop bc
+
+ ld a, [hJoyDown]
+ cp D_UP | SELECT | B_BUTTON
+ jr z, .asm_a34
+
+ ld a, [$ffa9]
+ and START | A_BUTTON
+ jr nz, .asm_a34
+
+ dec c
+ jr nz, Functiona1b
+
+ and a
+ ret
+
+.asm_a34
+ scf
+ ret
+; a36
+
+
+Functiona36: ; a36
+ call DelayFrame
+ call GetJoypadPublic
+ ld a, [hJoyPressed]
+ and A_BUTTON | B_BUTTON
+ ret nz
+ call RTC
+ jr Functiona36
+; a46
+
+Functiona46: ; a46
+ ld a, [hOAMUpdate]
+ push af
+ ld a, 1
+ ld [hOAMUpdate], a
+ call WaitBGMap
+ call Functiona36
+ pop af
+ ld [hOAMUpdate], a
+ ret
+; a57
+
+Functiona57: ; a57
+ call GetJoypadPublic
+ ld a, [$ffaa]
+ and a
+ ld a, [hJoyPressed]
+ jr z, .asm_a63
+ ld a, [hJoyDown]
+.asm_a63
+ ld [$ffa9], a
+ ld a, [hJoyPressed]
+ and a
+ jr z, .asm_a70
+ ld a, 15
+ ld [TextDelayFrames], a
+ ret
+
+.asm_a70
+ ld a, [TextDelayFrames]
+ and a
+ jr z, .asm_a7a
+ xor a
+ ld [$ffa9], a
+ ret
+
+.asm_a7a
+ ld a, 5
+ ld [TextDelayFrames], a
+ ret
+; a80
+
+Functiona80: ; a80
+ ld a, [$ffaf]
+ push af
+ ld a, [$ffb0]
+ push af
+ xor a
+ ld [$ffaf], a
+ ld a, $6
+ ld [$ffb0], a
+.asm_a8d
+ push hl
+ ld hl, $c606
+ call Functionb06
+ pop hl
+ call Functiona57
+ ld a, [$ffa9]
+ and $3
+ jr z, .asm_a8d
+ pop af
+ ld [$ffb0], a
+ pop af
+ ld [$ffaf], a
+ ret
+; aa5
+
+Functionaa5: ; aa5
+ call Functiona57
+ ld a, [$ffa9]
+ and A_BUTTON | B_BUTTON
+ jr z, Functionaa5
+ ret
+; aaf
+
+Functionaaf: ; aaf
+ ld a, [InLinkBattle]
+ and a
+ jr nz, .asm_ac1
+ call Functionac6
+ push de
+ ld de, SFX_READ_TEXT_2
+ call StartSFX
+ pop de
+ ret
+
+.asm_ac1
+ ld c, 65
+ jp DelayFrames
+; ac6
+
+Functionac6: ; ac6
+ ld a, [hOAMUpdate]
+ push af
+ ld a, $1
+ ld [hOAMUpdate], a
+ ld a, [InputType]
+ or a
+ jr z, .asm_ad9
+ callba Function1de28a
+.asm_ad9
+ call Functionaf5
+ call Functiona57
+ ld a, [hJoyPressed]
+ and $3
+ jr nz, .asm_af1
+ call RTC
+ ld a, $1
+ ld [hBGMapMode], a
+ call DelayFrame
+ jr .asm_ad9
+
+.asm_af1
+ pop af
+ ld [hOAMUpdate], a
+ ret
+; af5
+
+Functionaf5: ; af5
+ ld a, [$ff9b]
+ and $10
+ jr z, .asm_aff
+ ld a, $ee
+ jr .asm_b02
+
+.asm_aff
+ ld a, [$c605]
+
+.asm_b02
+ ld [$c606], a
+ ret
+; b06
+
+Functionb06: ; b06
+ push bc
+ ld a, [hl]
+ ld b, a
+ ld a, $ee
+ cp b
+ pop bc
+ jr nz, .asm_b27
+ ld a, [$ffaf]
+ dec a
+ ld [$ffaf], a
+ ret nz
+ ld a, [$ffb0]
+ dec a
+ ld [$ffb0], a
+ ret nz
+ ld a, $7a
+ ld [hl], a
+ ld a, $ff
+ ld [$ffaf], a
+ ld a, $6
+ ld [$ffb0], a
+ ret
+
+.asm_b27
+ ld a, [$ffaf]
+ and a
+ ret z
+ dec a
+ ld [$ffaf], a
+ ret nz
+ dec a
+ ld [$ffaf], a
+ ld a, [$ffb0]
+ dec a
+ ld [$ffb0], a
+ ret nz
+ ld a, $6
+ ld [$ffb0], a
+ ld a, $ee
+ ld [hl], a
+ ret
+; b40
+