There are a couple of things that the customer can try, as well as verify:
1) Make certain that the printer has not been previously communicating to a
Macintosh within the current power cycle. If so, the LaserWriter Select
310 driver puts the printer into a special serial communications mode.
To solve this, turn off the power to the printer, then turn it back on.
2) Set the communications on the Sun for:
57.6 Kbaud (try 38.4 Kbaud if 57.6 fails), two stop bits, no parity,
8 data bits
3) Verify that the PostScript code, or the driver generating it, is
producing good code. You might try sending the code to another printer.
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