diff options
Diffstat (limited to 'home/serial.asm')
| -rw-r--r-- | home/serial.asm | 617 |
1 files changed, 313 insertions, 304 deletions
diff --git a/home/serial.asm b/home/serial.asm index 02eb3534..fa3d4c8a 100644 --- a/home/serial.asm +++ b/home/serial.asm @@ -1,304 +1,313 @@ -Serial:: ; 2125 (0:2125) - push af - push bc - push de - push hl - ld a, [$ffaa] - inc a - jr z, .asm_2142 - ld a, [$ff01] - ld [$ffad], a - ld a, [$ffac] - ld [$ff01], a - ld a, [$ffaa] - cp $2 - jr z, .asm_2162 - ld a, $80 - ld [$ff02], a - jr .asm_2162 -.asm_2142 - ld a, [$ff01] - ld [$ffad], a - ld [$ffaa], a - cp $2 - jr z, .asm_215f - xor a - ld [$ff01], a - ld a, $3 - ld [rDIV], a ; $ff04 -.asm_2153 - ld a, [rDIV] ; $ff04 - bit 7, a - jr nz, .asm_2153 - ld a, $80 - ld [$ff02], a - jr .asm_2162 -.asm_215f - xor a - ld [$ff01], a -.asm_2162 - ld a, $1 - ld [$ffa9], a - ld a, $fe - ld [$ffac], a - pop hl - pop de - pop bc - pop af - reti - -Func_216f:: ; 216f (0:216f) - ld a, $1 - ld [$ffab], a -.asm_2173 - ld a, [hl] - ld [$ffac], a - call Func_219a - push bc - ld b, a - inc hl - ld a, $30 -.asm_217e - dec a - jr nz, .asm_217e - ld a, [$ffab] - and a - ld a, b - pop bc - jr z, .asm_2192 - dec hl - cp $fd - jr nz, .asm_2173 - xor a - ld [$ffab], a - jr .asm_2173 -.asm_2192 - ld [de], a - inc de - dec bc - ld a, b - or c - jr nz, .asm_2173 - ret - -Func_219a:: ; 219a (0:219a) - xor a - ld [$ffa9], a - ld a, [$ffaa] - cp $2 - jr nz, .asm_21a7 - ld a, $81 - ld [$ff02], a -.asm_21a7 - ld a, [$ffa9] - and a - jr nz, .asm_21f1 - ld a, [$ffaa] - cp $1 - jr nz, .asm_21cc - call Func_2237 - jr z, .asm_21cc - call Func_2231 - push hl - ld hl, wcc48 - inc [hl] - jr nz, .asm_21c3 - dec hl - inc [hl] -.asm_21c3 - pop hl - call Func_2237 - jr nz, .asm_21a7 - jp Func_223f -.asm_21cc - ld a, [rIE] ; $ffff - and $f - cp $8 - jr nz, .asm_21a7 - ld a, [W_NUMHITS] ; wd074 - dec a - ld [W_NUMHITS], a ; wd074 - jr nz, .asm_21a7 - ld a, [wd075] - dec a - ld [wd075], a - jr nz, .asm_21a7 - ld a, [$ffaa] - cp $1 - jr z, .asm_21f1 - ld a, $ff -.asm_21ee - dec a - jr nz, .asm_21ee -.asm_21f1 - xor a - ld [$ffa9], a - ld a, [rIE] ; $ffff - and $f - sub $8 - jr nz, .asm_2204 - ld [W_NUMHITS], a ; wd074 - ld a, $50 - ld [wd075], a -.asm_2204 - ld a, [$ffad] - cp $fe - ret nz - call Func_2237 - jr z, .asm_221f - push hl - ld hl, wcc48 - ld a, [hl] - dec a - ld [hld], a - inc a - jr nz, .asm_2219 - dec [hl] -.asm_2219 - pop hl - call Func_2237 - jr z, Func_223f -.asm_221f - ld a, [rIE] ; $ffff - and $f - cp $8 - ld a, $fe - ret z - ld a, [hl] - ld [$ffac], a - call DelayFrame - jp Func_219a - -Func_2231:: ; 2231 (0:2231) - ld a, $f -.asm_2233 - dec a - jr nz, .asm_2233 - ret - -Func_2237:: ; 2237 (0:2237) - push hl - ld hl, wcc47 - ld a, [hli] - or [hl] - pop hl - ret - -Func_223f:: ; 223f (0:223f) - dec a - ld [wcc47], a - ld [wcc48], a - ret - -Func_2247:: ; 2247 (0:2247) - ld hl, wcc42 - ld de, wcc3d - ld c, $2 - ld a, $1 - ld [$ffab], a -.asm_2253 - call DelayFrame - ld a, [hl] - ld [$ffac], a - call Func_219a - ld b, a - inc hl - ld a, [$ffab] - and a - ld a, $0 - ld [$ffab], a - jr nz, .asm_2253 - ld a, b - ld [de], a - inc de - dec c - jr nz, .asm_2253 - ret - -Func_226e:: ; 226e (0:226e) - call SaveScreenTilesToBuffer1 - callab PrintWaitingText - call Func_227f - jp LoadScreenTilesFromBuffer1 - -Func_227f:: ; 227f (0:227f) - ld a, $ff - ld [wcc3e], a -.asm_2284 - call Func_22c3 - call DelayFrame - call Func_2237 - jr z, .asm_22a0 - push hl - ld hl, wcc48 - dec [hl] - jr nz, .asm_229f - dec hl - dec [hl] - jr nz, .asm_229f - pop hl - xor a - jp Func_223f -.asm_229f - pop hl -.asm_22a0 - ld a, [wcc3e] - inc a - jr z, .asm_2284 - ld b, $a -.asm_22a8 - call DelayFrame - call Func_22c3 - dec b - jr nz, .asm_22a8 - ld b, $a -.asm_22b3 - call DelayFrame - call Func_22ed - dec b - jr nz, .asm_22b3 - ld a, [wcc3e] - ld [wcc3d], a - ret - -Func_22c3:: ; 22c3 (0:22c3) - call asm_22d7 - ld a, [wcc42] - add $60 - ld [$ffac], a - ld a, [$ffaa] - cp $2 - jr nz, asm_22d7 - ld a, $81 - ld [$ff02], a -asm_22d7:: ; 22d7 (0:22d7) - ld a, [$ffad] - ld [wcc3d], a - and $f0 - cp $60 - ret nz - xor a - ld [$ffad], a - ld a, [wcc3d] - and $f - ld [wcc3e], a - ret - -Func_22ed:: ; 22ed (0:22ed) - xor a - ld [$ffac], a - ld a, [$ffaa] - cp $2 - ret nz - ld a, $81 - ld [$ff02], a - ret - -Func_22fa:: ; 22fa (0:22fa) - ld a, $2 - ld [$ff01], a - xor a - ld [$ffad], a - ld a, $80 - ld [$ff02], a - ret +Serial:: ; 2125 (0:2125)
+ push af
+ push bc
+ push de
+ push hl
+ ld a, [hSerialConnectionStatus]
+ inc a
+ jr z, .connectionNotYetEstablished
+ ld a, [rSB]
+ ld [hSerialReceiveData], a
+ ld a, [hSerialSendData]
+ ld [rSB], a
+ ld a, [hSerialConnectionStatus]
+ cp USING_INTERNAL_CLOCK
+ jr z, .done
+; using external clock
+ ld a, START_TRANSFER_EXTERNAL_CLOCK
+ ld [rSC], a
+ jr .done
+.connectionNotYetEstablished
+ ld a, [rSB]
+ ld [hSerialReceiveData], a
+ ld [hSerialConnectionStatus], a
+ cp USING_INTERNAL_CLOCK
+ jr z, .usingInternalClock
+; using external clock
+ xor a
+ ld [rSB], a
+ ld a, $3
+ ld [rDIV], a
+.waitLoop
+ ld a, [rDIV]
+ bit 7, a
+ jr nz, .waitLoop
+ ld a, START_TRANSFER_EXTERNAL_CLOCK
+ ld [rSC], a
+ jr .done
+.usingInternalClock
+ xor a
+ ld [rSB], a
+.done
+ ld a, $1
+ ld [hSerialReceivedNewData], a
+ ld a, SERIAL_NO_DATA_BYTE
+ ld [hSerialSendData], a
+ pop hl
+ pop de
+ pop bc
+ pop af
+ reti
+
+; hl = send data
+; de = receive data
+; bc = length of data
+Serial_ExchangeBytes:: ; 216f (0:216f)
+ ld a, 1
+ ld [hSerialIgnoringInitialData], a
+.loop
+ ld a, [hl]
+ ld [hSerialSendData], a
+ call Serial_ExchangeByte
+ push bc
+ ld b, a
+ inc hl
+ ld a, 48
+.waitLoop
+ dec a
+ jr nz, .waitLoop
+ ld a, [hSerialIgnoringInitialData]
+ and a
+ ld a, b
+ pop bc
+ jr z, .storeReceivedByte
+ dec hl
+ cp SERIAL_PREAMBLE_BYTE
+ jr nz, .loop
+ xor a
+ ld [hSerialIgnoringInitialData], a
+ jr .loop
+.storeReceivedByte
+ ld [de], a
+ inc de
+ dec bc
+ ld a, b
+ or c
+ jr nz, .loop
+ ret
+
+Serial_ExchangeByte:: ; 219a (0:219a)
+ xor a
+ ld [hSerialReceivedNewData], a
+ ld a, [hSerialConnectionStatus]
+ cp USING_INTERNAL_CLOCK
+ jr nz, .asm_21a7
+ ld a, START_TRANSFER_INTERNAL_CLOCK
+ ld [rSC], a
+.asm_21a7
+ ld a, [hSerialReceivedNewData]
+ and a
+ jr nz, .asm_21f1
+ ld a, [hSerialConnectionStatus]
+ cp USING_EXTERNAL_CLOCK
+ jr nz, .asm_21cc
+ call IsUnknownCounterZero
+ jr z, .asm_21cc
+ call WaitLoop_15Iterations
+ push hl
+ ld hl, wUnknownSerialCounter + 1
+ inc [hl]
+ jr nz, .asm_21c3
+ dec hl
+ inc [hl]
+.asm_21c3
+ pop hl
+ call IsUnknownCounterZero
+ jr nz, .asm_21a7
+ jp SetUnknownCounterToFFFF
+.asm_21cc
+ ld a, [rIE]
+ and (1 << SERIAL) | (1 << TIMER) | (1 << LCD_STAT) | (1 << VBLANK)
+ cp (1 << SERIAL)
+ jr nz, .asm_21a7
+ ld a, [wUnknownSerialCounter2]
+ dec a
+ ld [wUnknownSerialCounter2], a
+ jr nz, .asm_21a7
+ ld a, [wUnknownSerialCounter2 + 1]
+ dec a
+ ld [wUnknownSerialCounter2 + 1], a
+ jr nz, .asm_21a7
+ ld a, [hSerialConnectionStatus]
+ cp USING_EXTERNAL_CLOCK
+ jr z, .asm_21f1
+ ld a, 255
+.waitLoop
+ dec a
+ jr nz, .waitLoop
+.asm_21f1
+ xor a
+ ld [hSerialReceivedNewData], a
+ ld a, [rIE]
+ and (1 << SERIAL) | (1 << TIMER) | (1 << LCD_STAT) | (1 << VBLANK)
+ sub (1 << SERIAL)
+ jr nz, .asm_2204
+ ld [wUnknownSerialCounter2], a
+ ld a, $50
+ ld [wUnknownSerialCounter2 + 1], a
+.asm_2204
+ ld a, [hSerialReceiveData]
+ cp SERIAL_NO_DATA_BYTE
+ ret nz
+ call IsUnknownCounterZero
+ jr z, .asm_221f
+ push hl
+ ld hl, wUnknownSerialCounter + 1
+ ld a, [hl]
+ dec a
+ ld [hld], a
+ inc a
+ jr nz, .asm_2219
+ dec [hl]
+.asm_2219
+ pop hl
+ call IsUnknownCounterZero
+ jr z, SetUnknownCounterToFFFF
+.asm_221f
+ ld a, [rIE]
+ and (1 << SERIAL) | (1 << TIMER) | (1 << LCD_STAT) | (1 << VBLANK)
+ cp (1 << SERIAL)
+ ld a, SERIAL_NO_DATA_BYTE
+ ret z
+ ld a, [hl]
+ ld [hSerialSendData], a
+ call DelayFrame
+ jp Serial_ExchangeByte
+
+WaitLoop_15Iterations:: ; 2231 (0:2231)
+ ld a, 15
+.waitLoop
+ dec a
+ jr nz, .waitLoop
+ ret
+
+IsUnknownCounterZero:: ; 2237 (0:2237)
+ push hl
+ ld hl, wUnknownSerialCounter
+ ld a, [hli]
+ or [hl]
+ pop hl
+ ret
+
+; a is always 0 when this is called
+SetUnknownCounterToFFFF:: ; 223f (0:223f)
+ dec a
+ ld [wUnknownSerialCounter], a
+ ld [wUnknownSerialCounter + 1], a
+ ret
+
+; 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:: ; 2247 (0:2247)
+ ld hl, wLinkMenuSelectionSendBuffer
+ ld de, wLinkMenuSelectionReceiveBuffer
+ ld c, 2 ; number of bytes to save
+ ld a, 1
+ ld [hSerialIgnoringInitialData], a
+.loop
+ call DelayFrame
+ ld a, [hl]
+ ld [hSerialSendData], a
+ call Serial_ExchangeByte
+ ld b, a
+ inc hl
+ ld a, [hSerialIgnoringInitialData]
+ and a
+ ld a, 0
+ ld [hSerialIgnoringInitialData], a
+ jr nz, .loop
+ ld a, b
+ ld [de], a
+ inc de
+ dec c
+ jr nz, .loop
+ ret
+
+Serial_PrintWaitingTextAndSyncAndExchangeByte:: ; 226e (0:226e)
+ call SaveScreenTilesToBuffer1
+ callab PrintWaitingText
+ call Serial_SyncAndExchangeNybble
+ jp LoadScreenTilesFromBuffer1
+
+Serial_SyncAndExchangeNybble:: ; 227f (0:227f)
+ ld a, $ff
+ ld [wSerialExchangeNybbleReceiveData], a
+.loop1
+ call Serial_ExchangeNybble
+ call DelayFrame
+ call IsUnknownCounterZero
+ jr z, .next1
+ push hl
+ ld hl, wUnknownSerialCounter + 1
+ dec [hl]
+ jr nz, .next2
+ dec hl
+ dec [hl]
+ jr nz, .next2
+ pop hl
+ xor a
+ jp SetUnknownCounterToFFFF
+.next2
+ pop hl
+.next1
+ ld a, [wSerialExchangeNybbleReceiveData]
+ inc a
+ jr z, .loop1
+ ld b, 10
+.loop2
+ call DelayFrame
+ call Serial_ExchangeNybble
+ dec b
+ jr nz, .loop2
+ ld b, 10
+.loop3
+ call DelayFrame
+ call Serial_SendZeroByte
+ dec b
+ jr nz, .loop3
+ ld a, [wSerialExchangeNybbleReceiveData]
+ ld [wSerialSyncAndExchangeNybbleReceiveData], a
+ ret
+
+; exchange one byte with value of $f or less
+Serial_ExchangeNybble:: ; 22c3 (0:22c3)
+ call .doExchange
+ ld a, [wSerialExchangeNybbleSendData]
+ add $60
+ ld [hSerialSendData], a
+ ld a, [hSerialConnectionStatus]
+ cp USING_INTERNAL_CLOCK
+ jr nz, .doExchange
+ ld a, START_TRANSFER_INTERNAL_CLOCK
+ ld [rSC], a
+.doExchange
+ ld a, [hSerialReceiveData]
+ ld [wSerialExchangeNybbleTempReceiveData], a
+ and $f0
+ cp $60
+ ret nz
+ xor a
+ ld [hSerialReceiveData], a
+ ld a, [wSerialExchangeNybbleTempReceiveData]
+ and $f
+ ld [wSerialExchangeNybbleReceiveData], a
+ ret
+
+Serial_SendZeroByte:: ; 22ed (0:22ed)
+ xor a
+ ld [hSerialSendData], a
+ ld a, [hSerialConnectionStatus]
+ cp USING_INTERNAL_CLOCK
+ ret nz
+ ld a, START_TRANSFER_INTERNAL_CLOCK
+ ld [rSC], a
+ ret
+
+Serial_TryEstablishingExternallyClockedConnection:: ; 22fa (0:22fa)
+ ld a, ESTABLISH_CONNECTION_WITH_EXTERNAL_CLOCK
+ ld [rSB], a
+ xor a
+ ld [hSerialReceiveData], a
+ ld a, START_TRANSFER_EXTERNAL_CLOCK
+ ld [rSC], a
+ ret
\ No newline at end of file |