'The Complete Spectrum ROM Disassembly' by Dr. Ian Logan and Dr. Frank O'Hara, as published by Melbourne House in 1983
The fact that they could publish a book like that is a nice reminder of how much the environment surrounding copyright/IP has changed since then... try to do that with the BIOS/firmware of a modern system today and, the issue of it being many times bigger aside, you'd probably just get DMCA'd.
I suppose companies back then were just far more open about and approving of users knowing how their systems worked; there's a similar book for the C64 (http://www.amazon.com/Complete-Commodore-Disassembly-Peter-G... ), and IBM even published the BIOS source code for its PC.
The fact that they could publish a book like that is a nice reminder of how much the environment surrounding copyright/IP has changed since then... try to do that with the BIOS/firmware of a modern system today and, the issue of it being many times bigger aside, you'd probably just get DMCA'd.
I suppose companies back then were just far more open about and approving of users knowing how their systems worked; there's a similar book for the C64 (http://www.amazon.com/Complete-Commodore-Disassembly-Peter-G... ), and IBM even published the BIOS source code for its PC.