Unicorn HAT Mini Remote I/O error

Hi, I just purchased a Unicorn HAT Mini to go with a Raspberry Pi Zero WH. When I try to run the example Python scripts following the instructions here, I get a ‘No ADC detected’ error (see below). I have tried two different Pis and tested Bullseye and Bookworm. The installation script set do_spi and do_i2c to 0, so I think those are good (and I did restart after those changes). I’ve also tried as a user and root with the same results. Thanks for any help you can provide.


This Automation HAT Mini example toggles and displays the
status of the three 24V-tolerant digital outputs.

Press CTRL+C to exit.

Traceback (most recent call last):
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/automationhat/__init__.py", line 367, in setup
    chip_type = _ads1015.detect_chip_type()
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/ads1015/__init__.py", line 70, in wrapper
    return func(self, *args, **kwargs)
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/ads1015/__init__.py", line 248, in detect_chip_type
    self._ads1015.set("CONFIG", mode="single")
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/i2cdevice/__init__.py", line 215, in set
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/i2cdevice/__init__.py", line 183, in read_register
    self.values[register.name] = self._i2c_read(register.address, register.bit_width)
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/i2cdevice/__init__.py", line 288, in _i2c_read
    for x in self._i2c.read_i2c_block_data(self._i2c_address, register, bit_width // self._bit_width):
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/smbus2/smbus2.py", line 617, in read_i2c_block_data
    ioctl(self.fd, I2C_SMBUS, msg)
OSError: [Errno 121] Remote I/O error

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/pi/Pimoroni/automationhat/examples/hat-mini/output.py", line 77, in <module>
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/automationhat/__init__.py", line 238, in write
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/automationhat/__init__.py", line 217, in setup
  File "/home/pi/.virtualenvs/pimoroni/lib/python3.9/site-packages/automationhat/__init__.py", line 369, in setup
    raise RuntimeError("No ADC detected, check your connections")
RuntimeError: No ADC detected, check your connections

The link you posted is for the Automation Hat, not the Unicorn Mini?
You want to be following this.
Getting Started with Unicorn HAT Mini (pimoroni.com)

Wow, I can’t believe I missed that. Thank you so much for getting me on the right track! It worked great when I followed the right guide :-)

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