The N64 development manual and SDK leaked a few years ago. Here's the documentation for the curious: <a href="http://level42.ca/projects/ultra64/Documentation/man/" rel="nofollow">http://level42.ca/projects/ultra64/Documentation/man/</a>
Even the mirror of the mirror doesn't load for me. Here is a Google-cached copy:<p><a href="http://webcache.googleusercontent.com/search?q=cache:_aGYRQKt5AIJ:n64.icequake.net/mirror/www.white-tower.demon.co.uk/n64/" rel="nofollow">http://webcache.googleusercontent.com/search?q=cache:_aGYRQK...</a>
A video tear down with a knowledgeable electrical engineer:
EEVblog #491 - Nintendo 64 Game Console Teardown<p><a href="https://www.youtube.com/watch?v=ScicrgZwvg4" rel="nofollow">https://www.youtube.com/watch?v=ScicrgZwvg4</a>