OSError : [Errno 121] Remote I/O error

Hello,

I'm approaching to IOPi by using tutorial2.py.

When i run command python tutorial2.py on RPi 3 B, this error is raised:

Traceback (most recent call last):
  File "/media/pi/OTTT/ABElectronics_Python_Libraries-master/IOPi/demos/tutorial2.py", line 60, in <module>
    main()
  File "/media/pi/OTTT/ABElectronics_Python_Libraries-master/IOPi/demos/tutorial2.py", line 52, in main
    if bus.read_pin(1) == 1:  # check to see if the button is pressed
  File "/usr/local/lib/python3.4/dist-packages/IOPi/IOPi.py", line 304, in read_pin
    self.__ioaddress, self.GPIOA)
OSError: [Errno 121] Remote I/O error

Any help?

Many thanks

Hello

A remote I/O error means that the python library is having trouble communicating with the IO Pi.

Please can you try running the command "sudo i2cdetect -y 1" and see what it returns? It should show a list of the devices on the I2C bus. The IO Pi Plus would normally show up on addresses 0x20 and 0x21.

If the IO Pi does not appear on the I2C bus or you get an error then I would recommend going through all of the steps in our I2C tutorial to make sure the I2C bus is configured correctly. Also, try checking the solder joints on the GPIO header to make sure there are no solder bridges between the pins or any dry joints.

Thanks for replying,

Actually, I configured the I2C bus using your official I2C tutorial and the "sudo i2cdetect -y 1" command returns this:





It seems to me that my IO Pi Plus I2C addresses are well affected.

The IO Pi is showing up on 0x20 and 0x21 so it should be working. Do you have any other devices connected to the I2C bus that may be using the same addresses?

Hello,

Thanks for your last answer. It makes me review the wiring. I was connecting RPi Display SDA and SCL to I2C pins which is not necessary. Now after removing them, it works perfectly.

Thank you again.