ESP32 Forum

The current TRM for the P4 (v1.3) still does not include Espressif's SIMD ISA extensions ("PIE"):

please refer to Chapter 2 Processor Instruction Extensions [to be added later].

I gather that most of the instructions work the same as the S3's, but the P4 has some new instructions and apparently abandoned some form the S3.
At least the differences to the S3 need to be documented somewhere.

Edit:
Just found
https://github.com/espressif/esp-idf/is ... 3392746085
which points to a TRM release in February (of 2026, I hope )

There was a blog post about the P4 PIE some time ago: https://developer.espressif.com/blog/20 ... roduction/

Most instructions still remain undocumented.