ESP32 Forum

Hello - I'm a novice. I watched https://www.youtube.com/c/BenEater 8-bit computer and now I want to write some assembly for the esp32.

I'm curious if there are resources to learn how to write a very basic set of instructions, flash them to the esp32, and get them executed.

For example, I'd like to setup the minimum chip functionality, check a GPIO for signal, turn on a led, and set a timer to interrupt and turn off the led.

I assume I need to write a couple instructions to a bin file, and copy that bin to flash on the esp32. Which flash? Which instruction does the esp32 begin reading from?

I don't want to use espidf or any other toolset at that high of a level. I just want to put bits on a flash and watch the cpu do something.

Any good resources to do this? Where do I start?

Best
Jon

Honestly, the Xtensa architecture underpinning the ESP32 is a bit of an odd beast, and there's no official documentation released by the owners of the arch when it comes to the low-level ISA... if you are going to try assembly, might I suggest grabbing an ESP32C3? That chip has a fancy new RiscV core, and as that architecture is all in the open, you should be able to find lots more information about it.

If you are interested in going with the ESP32-C3, the README on this product https://github.com/wuxx/nanoESP32-C3 seems to have all the important features.
It was the first one google came up with for me.

I’m having fun with this tutorial from Western Digital https://youtube.com/playlist?list=PL6no ... rXImHXMuLY
riscv ISA IMC32 like the C3 but more expensive hardware $60
https://www.sifive.com/boards/hifive1-rev-b
Espressif isn’t total left out as they provide wireless with ESP32-solo device.
You can step into the code with visual debugging. I’ve only got gdb/openocd to work with the ESP32-C3 which is tedious. And you need to hack up a USB cable.
The tutorial is for an older version of the board. Just remember to specify the Rev B version to PlatformIO.

Edit: Sorry. The Mouser #: 392-CS-HIFIVEB-01 is out of stock until Feb 2022