The Personal LaserWriter NT was not designed with the necessary intelligence to handle print jobs from both ports simultaneously. This would require an internal spooler that could queue print jobs from either port. It would probably also need to handle switching between PostScript and different emulations on the fly for this to be useful. You have two possible solutions: an external switching device or a different printer.
One such external device is a third-party product called BridgePort, by Extended Systems Inc. BridgePort lets any PostScript printer (including all of Apple's) accept jobs from a serial, parallel, or LocalTalk port. This external device automatically switches input to either a serial or parallel output to the PostScript printer. It is limited to accepting PostScript jobs only; it can't switch between HP and PostScript.
The LaserWriter Pro printers from Apple are capable of accepting print jobs from different ports without any additional hardware or software switching.
Article Change History:
21 Nov 1994 - Reviewed for technical accuracy.
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