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, 12 ld [wPrinterOpcode], a ; handshake ld a, $88 ldh [rSB], a ; switch to internal clock ld a, %00000001 ldh [rSC], a ; start transfer ld a, %10000001 ldh [rSC], a ret