diff options
Diffstat (limited to 'home/serial.asm')
| -rw-r--r-- | home/serial.asm | 169 |
1 files changed, 92 insertions, 77 deletions
diff --git a/home/serial.asm b/home/serial.asm index bd51084e..0fb1750b 100644 --- a/home/serial.asm +++ b/home/serial.asm @@ -1,4 +1,6 @@ -Serial:: ; 6aa (0:06aa) +Serial:: +; The serial interrupt. + push af push bc push de @@ -9,18 +11,22 @@ Serial:: ; 6aa (0:06aa) jr nz, .printer ldh a, [hLinkPlayerNumber] - inc a - jr z, .init_player_number + inc a ; is it equal to CONNECTION_NOT_ESTABLISHED? + jr z, .establish_connection + ldh a, [rSB] ldh [hSerialReceive], a + ldh a, [hSerialSend] ldh [rSB], a + ldh a, [hLinkPlayerNumber] - cp $2 + cp USING_INTERNAL_CLOCK jr z, .player2 - ld a, 0 << rSC_ON + + ld a, (0 << rSC_ON) | (0 << rSC_CLOCK) ldh [rSC], a - ld a, 1 << rSC_ON + ld a, (1 << rSC_ON) | (0 << rSC_CLOCK) ldh [rSC], a jr .player2 @@ -28,22 +34,22 @@ Serial:: ; 6aa (0:06aa) call PrinterReceive jr .end -.init_player_number +.establish_connection ldh a, [rSB] - cp $1 + cp USING_EXTERNAL_CLOCK jr z, .player1 - cp $2 + cp USING_INTERNAL_CLOCK jr nz, .player2 .player1 ldh [hSerialReceive], a ldh [hLinkPlayerNumber], a - cp $2 + cp USING_INTERNAL_CLOCK jr z, ._player2 xor a ldh [rSB], a - ld a, $3 + ld a, 3 ldh [rDIV], a .wait_bit_7 @@ -51,18 +57,19 @@ Serial:: ; 6aa (0:06aa) bit 7, a jr nz, .wait_bit_7 - ; cycle the serial controller - ld a, 0 << rSC_ON + ; Cycle the serial controller + ld a, (0 << rSC_ON) | (0 << rSC_CLOCK) ldh [rSC], a - ld a, 1 << rSC_ON + ld a, (1 << rSC_ON) | (0 << rSC_CLOCK) ldh [rSC], a jr .player2 ._player2 xor a ldh [rSB], a + .player2 - ld a, $1 + ld a, TRUE ldh [hFFCC], a ld a, SERIAL_NO_DATA_BYTE ldh [hSerialSend], a @@ -74,13 +81,13 @@ Serial:: ; 6aa (0:06aa) pop af reti -Function710:: ; 710 - ld a, $1 +Serial_ExchangeBytes:: + ld a, 1 ldh [hFFCE], a .loop ld a, [hl] ldh [hSerialSend], a - call Function73b + call Serial_ExchangeByte push bc ld b, a inc hl @@ -109,27 +116,29 @@ Function710:: ; 710 jr nz, .loop ret -Function73b:: ; 73b (0:073b) +Serial_ExchangeByte:: .loop xor a ldh [hFFCC], a ldh a, [hLinkPlayerNumber] - cp $2 - jr nz, .loop2 - ld a, (1 << rSC_CLOCK) | (0 << rSC_ON) + cp 2 + jr nz, .not_player_2 + ld a, (0 << rSC_ON) | (1 << rSC_CLOCK) ldh [rSC], a - ld a, (1 << rSC_CLOCK) | (1 << rSC_ON) + ld a, (1 << rSC_ON) | (1 << rSC_CLOCK) ldh [rSC], a + +.not_player_2 .loop2 ldh a, [hFFCC] and a jr nz, .reset_ffcc ldh a, [hLinkPlayerNumber] - cp $1 + cp 1 jr nz, .not_player_1_or_wLinkTimeoutFrames_zero - call CheckLinkTimeout + call CheckwLinkTimeoutFramesNonzero jr z, .not_player_1_or_wLinkTimeoutFrames_zero - call Serial15CycleDelay + call .delay_15_cycles push hl ld hl, wLinkTimeoutFrames + 1 inc [hl] @@ -139,14 +148,14 @@ Function73b:: ; 73b (0:073b) .no_rollover_up pop hl - call CheckLinkTimeout + call CheckwLinkTimeoutFramesNonzero jr nz, .loop2 jp SerialDisconnected .not_player_1_or_wLinkTimeoutFrames_zero ldh a, [rIE] - and $f - cp $8 + and (1 << SERIAL) | (1 << TIMER) | (1 << LCD_STAT) | (1 << VBLANK) + cp 1 << SERIAL jr nz, .loop2 ld a, [wce5d] dec a @@ -157,10 +166,10 @@ Function73b:: ; 73b (0:073b) ld [wce5d + 1], a jr nz, .loop2 ldh a, [hLinkPlayerNumber] - cp $1 + cp 1 jr z, .reset_ffcc - - ld a, $ff + + ld a, 255 .delay_255_cycles dec a jr nz, .delay_255_cycles @@ -169,20 +178,21 @@ Function73b:: ; 73b (0:073b) xor a ldh [hFFCC], a ldh a, [rIE] - and $f - sub $8 + and (1 << SERIAL) | (1 << TIMER) | (1 << LCD_STAT) | (1 << VBLANK) + sub 1 << SERIAL jr nz, .rIE_not_equal_8 + ; LOW($5000) ld [wce5d], a - ld a, 80 + ld a, HIGH($5000) ld [wce5d + 1], a .rIE_not_equal_8 ldh a, [hSerialReceive] cp SERIAL_NO_DATA_BYTE ret nz - call CheckLinkTimeout - jr z, .link_timed_out + call CheckwLinkTimeoutFramesNonzero + jr z, .linkTimeoutFrames_zero push hl ld hl, wLinkTimeoutFrames + 1 ld a, [hl] @@ -194,13 +204,13 @@ Function73b:: ; 73b (0:073b) .no_rollover pop hl - call CheckLinkTimeout + call CheckwLinkTimeoutFramesNonzero jr z, SerialDisconnected -.link_timed_out +.linkTimeoutFrames_zero ldh a, [rIE] - and $f - cp $8 + and (1 << SERIAL) | (1 << TIMER) | (1 << LCD_STAT) | (1 << VBLANK) + cp 1 << SERIAL ld a, SERIAL_NO_DATA_BYTE ret z ld a, [hl] @@ -208,14 +218,14 @@ Function73b:: ; 73b (0:073b) call DelayFrame jp .loop -Serial15CycleDelay:: ; 7d6 (0:07d6) - ld a, $f -.loop +.delay_15_cycles + ld a, 15 +.delay_cycles dec a - jr nz, .loop + jr nz, .delay_cycles ret -CheckLinkTimeout:: ; 7dc (0:07dc) +CheckwLinkTimeoutFramesNonzero:: push hl ld hl, wLinkTimeoutFrames ld a, [hli] @@ -223,28 +233,30 @@ CheckLinkTimeout:: ; 7dc (0:07dc) pop hl ret -SerialDisconnected:: ; 7e4 (0:07e4) - dec a +SerialDisconnected:: + dec a ; a is always 0 when this is called ld [wLinkTimeoutFrames], a ld [wLinkTimeoutFrames + 1], a ret -Function7ec:: ; 7ec +; This is used to exchange the button press and selected menu item on the link menu. +; The data is sent thrice and read twice to increase reliability. +Serial_ExchangeLinkMenuSelection:: ld hl, wPlayerLinkAction ld de, wOtherPlayerLinkMode - ld c, $2 - ld a, $1 + ld c, 2 + ld a, TRUE ldh [hFFCE], a .asm_7f8 call DelayFrame ld a, [hl] ldh [hSerialSend], a - call Function73b + call Serial_ExchangeByte ld b, a inc hl ldh a, [hFFCE] and a - ld a, $0 + ld a, 0 ldh [hFFCE], a jr nz, .asm_7f8 ld a, b @@ -254,26 +266,26 @@ Function7ec:: ; 7ec jr nz, .asm_7f8 ret -Function813:: ; 813 - call LoadTileMapToTempTileMap +Serial_PrintWaitingTextAndSyncAndExchangeNybble:: + call LoadTilemapToTempTilemap callfar PlaceWaitingText call WaitLinkTransfer - jp Call_LoadTempTileMapToTileMap + jp SafeLoadTempTilemapToTilemap -Function822:: ; 822 - call LoadTileMapToTempTileMap +Serial_SyncAndExchangeNybble:: + call LoadTilemapToTempTilemap callfar PlaceWaitingText jp WaitLinkTransfer ; One "giant" leap for machinekind -WaitLinkTransfer:: ; 82e (0:082e) +WaitLinkTransfer:: ld a, $ff ld [wOtherPlayerLinkAction], a .loop call LinkTransfer call DelayFrame - call CheckLinkTimeout + call CheckwLinkTimeoutFramesNonzero jr z, .check push hl ld hl, wLinkTimeoutFrames + 1 @@ -282,6 +294,7 @@ WaitLinkTransfer:: ; 82e (0:082e) dec hl dec [hl] jr nz, .skip + ; We might be disconnected pop hl xor a jp SerialDisconnected @@ -312,7 +325,7 @@ WaitLinkTransfer:: ; 82e (0:082e) ld [wOtherPlayerLinkMode], a ret -LinkTransfer:: ; 872 (0:0872) +LinkTransfer:: push bc ld b, SERIAL_TIMECAPSULE ld a, [wLinkMode] @@ -326,23 +339,24 @@ LinkTransfer:: ; 872 (0:0872) ld b, SERIAL_BATTLE .got_high_nybble - call LinkTransferReceive + call .Receive ld a, [wPlayerLinkAction] add b ldh [hSerialSend], a ldh a, [hLinkPlayerNumber] - cp $2 - jr nz, .asm_89f - ld a, $1 + cp USING_INTERNAL_CLOCK + jr nz, .player_1 + ld a, (0 << rSC_ON) | (1 << rSC_CLOCK) ldh [rSC], a - ld a, $81 + ld a, (1 << rSC_ON) | (1 << rSC_CLOCK) ldh [rSC], a -.asm_89f - call LinkTransferReceive + +.player_1 + call .Receive pop bc ret -LinkTransferReceive:: ; 8a4 (0:08a4) +.Receive: ldh a, [hSerialReceive] ld [wOtherPlayerLinkMode], a and $f0 @@ -355,28 +369,29 @@ LinkTransferReceive:: ; 8a4 (0:08a4) ld [wOtherPlayerLinkAction], a ret -LinkDataReceived:: ; 8b9 (0:08b9) +LinkDataReceived:: +; Let the other system know that the data has been received. xor a ldh [hSerialSend], a ldh a, [hLinkPlayerNumber] - cp $2 + cp USING_INTERNAL_CLOCK ret nz - ld a, $1 + ld a, (0 << rSC_ON) | (1 << rSC_CLOCK) ldh [rSC], a - ld a, $81 + ld a, (1 << rSC_ON) | (1 << rSC_CLOCK) ldh [rSC], a ret -Function8ca:: ; 8ca +Unreferenced_Function8ca:: ld a, [wLinkMode] and a ret nz - ld a, $2 + ld a, USING_INTERNAL_CLOCK ldh [rSB], a xor a ldh [hSerialReceive], a - ld a, $0 + ld a, (0 << rSC_ON) | (0 << rSC_CLOCK) ldh [rSC], a - ld a, $80 + ld a, (1 << rSC_ON) | (0 << rSC_CLOCK) ldh [rSC], a ret |