It is possible to connect a Macintosh to a LaserWriter and print using a serial cable in many instances, but Apple recommends the use of properly terminated LocalTalk cabling to ensure a working connection. The RS-422 (serial) port on LaserWriters manufactured after the LaserWriter Plus is normally used for LocalTalk and can be identified by its mini-circular 8 port.
Here is a partial list of LaserWriter printers Apple supports using a Peripheral 8 serial cable.
LaserWriter Pro 600
LaserWriter Pro 630
LaserWriter Pro 810
LaserWriter Select 300
LaserWriter Select 310 (This print only supports a Macintosh serial cable)
LaserWriter Select 360
Personal LaserWriter LS
Personal LaserWriter 300
LaserWriter 4/600 PS
LaserWriter 16/600 PS
Consult your LaserWriter User's Guide, it contains connection instructions. If your LaserWriter printer supports serial printing, instructions are provided.
The one drawback to a serial connection on LaserWriter printers designed for LocalTalk is that you lose access to other network services since the LocalTalk port is being used by the serial cable.
Note: Reference the User's Guide for correct printer port settings. You may have to change the pushwheel number or the dip switches.
The finished goods part number for the Peripheral 8 serial cable is M0197, the service part number is 590-0522.