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