If you have the red ROM for the AITB (Set Top Box/STB), the one that displays on the composite outputs, you can actually hack the unusual form of System 7.1 it includes in ROM. It works great with a BMOW 2MB ROM-inator and a SIMM programmer.
Apple's Interactive Television Box: hacking the Set Top Box System 7.1 in ROM
This article has been revised with recollections and corrections from former Apple employee Al Kossow, some good folks on Hacker News and t...
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