Thanks for the report. It's definitely something that needs to be fixed.

I'm working on that one (should have it soon), but currently focusing on finishing S2/S3 support.

For now you could use mpremote on a PC to copy the necessary files to your ESP32.

First clone this repo, then from within the repo root, run:

pip install mpremote  #if not yet installed
mpremote cp -r esp32_ulp :

Then it will work.

Potentially this would work too (I havent tested it, but I made the necessary package.json available as a Gist):

# on the ESP32
# make sure network is connected
import mip
mip.install("https://gist.githubusercontent.com/wnienhaus/5a30dd2ac7000764b065b44c5341f1e9/raw/54e1d43dbb0761b10134a34ca70d272064b66987/package.json")

Potentially this would work too (I havent tested it, but I made the necessary package.json available as a Gist):

# on the ESP32
# make sure network is connected
import mip
mip.install("https://gist.githubusercontent.com/wnienhaus/5a30dd2ac7000764b065b44c5341f1e9/raw/54e1d43dbb0761b10134a34ca70d272064b66987/package.json")

Wow thanks for the fast reply!

Your command almost worked:

>>> import mip
>>> mip.install("https://gist.githubusercontent.com/wnienhaus/5a30dd2ac7000764b065b44c5341f1e9/raw/54e1d43dbb0761b10134a34ca70d272064b66987/package.json")
Installing https://gist.githubusercontent.com/wnienhaus/5a30dd2ac7000764b065b44c5341f1e9/raw/54e1d43dbb0761b10134a34ca70d272064b66987/package.json to /lib
Copying: /lib/esp32_ulp/__init__.py
Copying: /lib/esp32_ulp/__main__.py
Copying: /lib/esp32_ulp/assemble.py
Copying: /lib/esp32_ulp/definesdb.py
Copying: /lib/esp32_ulp/link.py
Copying: /lib/esp32_ulp/nocomment.py
Copying: /lib/esp32_ulp/opcodes.py
Copying: /lib/esp32_ulp/parse_to_db.py
Copying: /lib/esp32_ulp/preprocess.py
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "mip/__init__.py", line 1, in install
  File "mip/__init__.py", line 1, in _install_package
  File "mip/__init__.py", line 1, in _install_json
  File "mip/__init__.py", line 1, in _download_file
  File "mip/__init__.py", line 1, in _chunk
OSError: -29184
>>> 

Potentially this would work too (I havent tested it, but I made the necessary package.json available as a Gist):

# on the ESP32
# make sure network is connected
import mip
mip.install("https://gist.githubusercontent.com/wnienhaus/5a30dd2ac7000764b065b44c5341f1e9/raw/54e1d43dbb0761b10134a34ca70d272064b66987/package.json")

Wow thanks for the fast reply!
Your command almost worked:

>>> import mip
>>> mip.install("https://gist.githubusercontent.com/wnienhaus/5a30dd2ac7000764b065b44c5341f1e9/raw/54e1d43dbb0761b10134a34ca70d272064b66987/package.json")
Installing https://gist.githubusercontent.com/wnienhaus/5a30dd2ac7000764b065b44c5341f1e9/raw/54e1d43dbb0761b10134a34ca70d272064b66987/package.json to /lib
Copying: /lib/esp32_ulp/__init__.py
Copying: /lib/esp32_ulp/__main__.py
Copying: /lib/esp32_ulp/assemble.py
Copying: /lib/esp32_ulp/definesdb.py
Copying: /lib/esp32_ulp/link.py
Copying: /lib/esp32_ulp/nocomment.py
Copying: /lib/esp32_ulp/opcodes.py
Copying: /lib/esp32_ulp/parse_to_db.py
Copying: /lib/esp32_ulp/preprocess.py
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "mip/__init__.py", line 1, in install
  File "mip/__init__.py", line 1, in _install_package
  File "mip/__init__.py", line 1, in _install_json
  File "mip/__init__.py", line 1, in _download_file
  File "mip/__init__.py", line 1, in _chunk
OSError: -29184
>>> 

Further after ignoring the oserror, and copying the example file counter.py, I got this:

>>> import counter
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "counter.py", line 15, in <module>
  File "/lib/esp32_ulp/__init__.py", line 1, in <module>
ImportError: no module named 'esp32_ulp.util'

I had to copy over util.py, which then results in:

>>> import counter
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "counter.py", line 15, in <module>
  File "/lib/esp32_ulp/__init__.py", line 3, in <module>
ImportError: can't import name preprocess
>>> 

ImportError: can't import name preprocess

this will be the same thing as util.py - the file did not get installed correctly.

Basically the mip install crashed while downloading preprocess.py so it and all files thereafter are corrupt/missing. You can see the full list of files that should have downloaded in the gist: (one more file that should have come after the mip crash during preprocess.py).

Make sure to manually copy all the missing files to the esp32_ulp directory on your ESP32.

ImportError: can't import name preprocess

this will be the same thing as util.py - the file did not get installed correctly.

Basically the mip install crashed while downloading preprocess.py so it and all files thereafter are corrupt/missing. You can see the full list of files that should have downloaded in the gist: (one more file that should have come after the mip crash during preprocess.py).

Make sure to manually copy all the missing files to the esp32_ulp directory on your ESP32.

This was exactly the problem thanks a bunch!

I'll reopen this, because one still cannot install using mip, and the latest MicroPython no longer has upip. (The above is just a workaround).
I'll add the necessary support next, by adding a valid package.json file and by updating the documentation.