CPU architecture reference manual

[jakehuang]

Hi guys, I wonder if we can access to the CPU architecture reference manual to esp32 dual core CPU similar to this
http://infocenter.arm.com/help/index.js ... index.html for ARM

As you know Xtensa is not popular like ARM where resources are abundant. If we have access to the architecture manual to the very CPU that's used in esp32, it would be of great value to hackers and makers alike because a lot of people will start contributing code to idf and freertos for esp32 developmenent instead of just waiting for expressif to do all the fundamental work.

[loboris]

Some documentation is available:
Xtensa_lx Overview handbook
Xtensa Instruction Set Architecture