An UPDATE: One our members kindly sent me the schematics and it shows all the signals that connect to J18.
He mentions kinda what I suspected, that if this logic board can't talk to the print controller, it reboots.
I recently bought a LaserWriter II-NTX logic board (Apple P/N 630-0158 with 8-out-of-12 SIMMs populated)
My crazy plan is to bring it up without the rest of the printer, so I can chat with the PostScript interpreter.
The LaserWriter II Repair Manual spends almost no time on the logic board.
(On...
I just read Crispin Goswell’s 1987 paper “An Implementstion of PostScript.” Besides the fact that I believe you intrinsically, this reminder of the complexity of the language itself and the graphics algorithms leads me to concur. My “monkey’s uncle” statement was an inference based on the vast...
Excellent. Let us know if-and-when you get around to disassembling them. If Adobe's first PostScript interpreter wasn't written in assembly language, "I'm a monkey's uncle."
The MAME community, already used to dumping arcade game ROMs has multiple LaserWriter ROMs in their collection:
http://adb.arcadeitalia.net/dettaglio_mame.php?game_name=lwriterplus