Compiling ULP Assembler Code How-To using ESP-IDF

[belveder79]

I'm trying to build some assembler code for the ULP module grabbing and modifying some example code from here. However, I can't really get anything working following the tutorial given here.

What it states is that using the Micropython-on-ESP32 is deprecated and should not be used, but I can't get the other things working either. I don't even get to the point where I could use this [binS2Berry.py](https://github.com/Staars/berry-examples/blob/main/ulp_helper/binS2Berry.py)?target=https://github.com because I can't get the assembler code to compile. What I did was:

• cloned the https://github.com/Staars/berry-examples?target=https://github.com repo
• created a plain ESP-IDF project with the original ExpressIf-Toolchain
• copied over the asm source from ulp_gpio_wake.py into a component wake_gpio.S and tried to compile

that fails with a ton of errors like

Compiling .pio/build/esp32dev/components/asms/wake_gpio.S.o
components/asms/wake_gpio.S: Assembler messages:
components/asms/wake_gpio.S:68: Error: unknown opcode or format name 'move'
components/asms/wake_gpio.S:69: Error: unknown opcode or format name 'ld'
components/asms/wake_gpio.S:75: Error: unknown opcode or format name 'move'
components/asms/wake_gpio.S:76: Error: unknown opcode or format name 'jumpr'
components/asms/wake_gpio.S:79: Error: unknown opcode or format name 'read_rtc_reg'
components/asms/wake_gpio.S:80: Error: unknown opcode or format name 'rsh'
components/asms/wake_gpio.S:81: Error: unknown opcode or format name 'jump'
components/asms/wake_gpio.S:85: Error: unknown opcode or format name 'read_rtc_reg'
components/asms/wake_gpio.S:86: Error: bad register name: r3
components/asms/wake_gpio.S:86: Error: bad register name: r3
components/asms/wake_gpio.S:86: Error: bad register name: 16
components/asms/wake_gpio.S:87: Error: unknown opcode or format name 'rsh'
...

Can someone provide an example project or setup to get this to work? Thx

[Staars]

Did you try the web app on this page:
https://tasmota.github.io/docs/ULP/#export-from-esp-idf-project

The only remaining way to use ULP is to build a ESP-IDF project and then to convert the resulting code.

I will check the current state, when I find the time. A few months ago it still did work, but sadly things can change.

[belveder79]

I tried, but since it already failed compiling on my side, I think it does not do anything useful for my case?

I don't remember where I read it, but on some issue forum on github someone wrote it was linked to the extensa compiler treating the .S file wrong. Not sure about that...

[belveder79]

Ok, got it to work (mostly):

• create a project in VSCode with PlatformIO, choosing ESPIDF as framework and an ESP32 as target
• follow ULPTool instructions and add code to ulp folder
• build - fails for me, but builds the asm code...
• Variant 1: choose .pio/<platformname> as the folder for the extractor
• Variant 2: use console in project folder, do ln -s .pio/build/<platformname> build and run python3 binS2Berry.py

Did not check if it works though...

[Staars]

After the Micropython way broke some time ago, I only ever did build a regular IDF project following the ULP examples from ESP-IDF. I never tried to do it in Platformio.