mirror of https://github.com/pret/pokecrystal.git
42 lines
594 B
NASM
42 lines
594 B
NASM
PrinterReceive::
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homecall _PrinterReceive
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ret
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AskSerial::
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; send out a handshake while serial int is off
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ld a, [wPrinterConnectionOpen]
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bit 0, a
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ret z
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; if we're still interpreting data, don't try to receive
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ld a, [wPrinterOpcode]
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and a
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ret nz
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; once every 6 frames
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ld hl, wHandshakeFrameDelay
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inc [hl]
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ld a, [hl]
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cp 6
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ret c
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xor a
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ld [hl], a
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ld a, 12
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ld [wPrinterOpcode], a
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; handshake
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ld a, $88
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ldh [rSB], a
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; switch to internal clock
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ld a, (0 << rSC_ON) | (1 << rSC_CLOCK)
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ldh [rSC], a
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; start transfer
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ld a, (1 << rSC_ON) | (1 << rSC_CLOCK)
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ldh [rSC], a
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ret
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