AttributeError: module 'board' has no attribute 'I2C'

[sumghai]

Summary of Issue

Attempting to initialize the class object from ServoKit results in the following error:

Traceback (most recent call last):
  File "servo_test.py", line 3, in <module>
    kit = ServoKit(channels=16)
  File "/usr/local/lib/python3.5/dist-packages/adafruit_servokit.py", line 85, in __init__
    i2c = board.I2C()
AttributeError: module 'board' has no attribute 'I2C'

Hardware

• Raspberry Pi 3 Model B
• Adafruit 16-Channel 12-bit PWM/Servo Driver - I2C interface - PCA9685
• (2x) GWS S03T STD Servos

Software and Environment

• Raspbian Stretch (Debian 9, Release 2018-11-13)
• Python 3
• Adafruit GPIO 1.0.3
• Adafruit Blinka 1.2.6 (I2C verified working with blinkatest.py example file)
• Adafruit CircuitPython ServoKit 1.1.0
• Installed and configured as per the 16 channel servo driver tutorial

servo_test.py

import time
from adafruit_servokit import ServoKit
kit = ServoKit(channels=16)

# Tuned for GWS S03T STD Servos
kit.servo[0].set_pulse_width_range(775, 2450)
kit.servo[1].set_pulse_width_range(775, 2450)

# Return servos to starting positions
kit.servo[0].angle = 0
kit.servo[1].angle = 180
time.sleep(1)

while True:
    for tgtAngle in range(0, 180, 1):
        kit.servo[0].angle = tgtAngle
        kit.servo[1].angle = 180 - tgtAngle
        time.sleep(0.1)
    for tgtAngle in range(180, 0, -1):
        kit.servo[0].angle = tgtAngle
        kit.servo[1].angle = 180 - tgtAngle
        time.sleep(0.1)

Notes

• I previously had CircuitPython ServoKit working with the Python code sample and two servos one week ago
• This morning, I had to completely reformat and re-setup my Raspberry Pi due to an unrelated issue
• After reinstalling CircuitPython ServoKit and all dependencies from scratch, I found that my existing code no longer works and instead returned the titular error message, so I presume there was a change in adafruit_servokit.py between my two installations
• Examining adafruit_servokit.py, I noticed that line 85 was previously (828a46c) defined as i2c = busio.I2C(board.SCL, board.SDA) instead of the current i2c = board.I2C(); perhaps this line may be of interest
• The blinkatest.py example currently still works because it uses the older i2c = busio.I2C(board.SCL, board.SDA)

[abhiTronix]

@sumghai Bug confirmed. Tested on my Raspberry Pi 3 Model B.

There is no documentation/comment anywhere related to the new i2c parameter introduced in the latest commit #6, like what should be its value? @kattni can you please help?

[kattni]

@sumghai @abhiTronix We were fixing a different I2C bug and introduced this one. This is fixed by adafruit/Adafruit_Blinka#95. Please update Adafruit_Blinka to resolve the issue. I've done a new release - give it a few minutes to deploy to PyPI before trying to update.

To answer your question, @abhiTronix, to pass in different pins, you would instantiate the library as follows:

import busio
from adafruit_servokit import ServoKit
kit = ServoKit(channels=16, i2c=(busio.I2C(board.SCL, board.SDA)))

I have only tested that on a microcontroller, not on RasPi, but that is the idea of how to pass in different I2C pins.

[sumghai]

I can confirm that updating Adafruit Blinka to 1.2.7 resolves this issue on the RasPi.

Thanks @kattni!

[hamwong]

HI,

I am trying to use below code on python3 and have same error

    import busio
    import adafruit_tsl2561
    i2c = busio.I2C(board.SCL, board.SDA)
    sensor = adafruit_tsl2561.TSL2561(i2c)

I am using Rpi 3B+ with Adafruit-Blinka 3.3.4

Name: Adafruit-Blinka
Version: 3.3.4
Summary: CircuitPython APIs for non-CircuitPython versions of Python such as CPython on Linux and MicroPython.
Home-page: https://github.com/adafruit/Adafruit_Blinka
Author: Adafruit Industries
Author-email: circuitpython@adafruit.com
License: MIT
Location: /usr/local/lib/python3.5/dist-packages
Requires: Adafruit-PlatformDetect, rpi-ws281x, spidev, RPi.GPIO, sysv-ipc, pyftdi, Adafruit-PureIO

I got below error

  File "./TSL2561c.py", line 12, in <module>
    i2c = busio.I2C(board.SCL, board.SDA)
AttributeError: module 'board' has no attribute 'SCL'

[caternuson]

You aren't importing board? But somehow it must be or the error would be different. What does this show?

import board
dir(board)

[hamwong]

You aren't importing board? But somehow it must be or the error would be different. What does this show?

import board
dir(board)

Sorry, I didn't double check the code I post, I have , it's at first line and I miss to copy it and paste here.
but I am 100% sure import board is there, I add your line and it didn't show alarm but I found further when print out, it looks my board have some problem

import time
import board
dir(board)
import busio
import adafruit_tsl2561
print("board contents: ", dir(board))
i2c = busio.I2C(board.SCL, board.SDA)
sensor = adafruit_tsl2561.TSL2561(i2c)

python3 TSL2561c.py
board contents:  ['BaseDimension', 'Board', 'Dimension', 'Empty', 'Image', 'InfiniteDimension', 'Infinity', '_Empty', '_InfiniteDimension', '_Infinity', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__', '_centred_coord', 'cornerposts', 'functools', 'imagefile_sprite', 'io', 'itertools', 'long', 'os', 'sys', 'text_sprite']
Traceback (most recent call last):
  File "TSL2561c.py", line 15, in <module>
    i2c = busio.I2C(board.SCL, board.SDA)
AttributeError: module 'board' has no attribute 'SCL'

I found other people should come out like this, what's wrong with my board
board contents: ['CE0', 'CE0_1', 'CE1', 'CE1_1', 'D10', 'D11', 'D12', 'D13', 'D16', 'D17', 'D18', 'D19', 'D20', 'D21', 'D22', 'D23', 'D24', 'D25', 'D26', 'D27', 'D4', 'D5', 'D6', 'D7', 'D8', 'D9', 'I2C', 'MISO', 'MISO_1', 'MOSI', 'MOSI_1', 'SCK', 'SCK_1', 'SCL', 'SCLK', 'SCLK_1', 'SCL_1', 'SDA', 'SDA_1', 'SPI', 'builtins', 'cached', 'doc', 'file', 'loader', 'name', 'package', 'spec', 'ap_board', 'board_id', 'detector', 'pin', 'sys']

pip3 list
Adafruit-Blinka (3.3.4)
adafruit-circuitpython-busdevice (4.1.0)
adafruit-circuitpython-lis3dh (5.0.1)
adafruit-circuitpython-tsl2561 (3.2.2)
Adafruit-PlatformDetect (1.3.8)
Adafruit-PureIO (1.0.4)
board (1.0)

[ladyada]

looks like you have some other library that has created a board.py in your python collection, & you'll have to remove it

[caternuson]

Yep. You somehow have this installed:
https://pypi.org/project/board/
instead of the board that comes with Blinka.

You can not install the board module individually. You need to do a complete Blinka install.

[hamwong]

Thanks @caternuson and @ladyada
after remove board and reinstall Blinka, work as expect.

[Nathanaelhend]

@hamwong solved?

[DvarfInkviz]

board contents: ['CE0', 'CE0_1', 'CE1', 'CE1_1', 'D10', 'D11', 'D12', 'D13', 'D16', 'D17', 'D18', 'D19', 'D20', 'D21', 'D22', 'D23', 'D24', 'D25', 'D26', 'D27', 'D4', 'D5', 'D6', 'D7', 'D8', 'D9', 'I2C', 'MISO', 'MISO_1', 'MOSI', 'MOSI_1', 'SCK', 'SCK_1', 'SCL', 'SCLK', 'SCLK_1', 'SCL_1', 'SDA', 'SDA_1', 'SPI', 'builtins', 'cached', 'doc', 'file', 'loader', 'name', 'package', 'spec', 'ap_board', 'board_id', 'detector', 'pin', 'sys']

Hello!

I use board NanoPi NEO CORE with Armbian_community 24.8.0-trunk.495 Noble with Linux 6.12.23-current-sunxi.
I need to work with bus I2C-2 for AHT10 temperature and humidity sensor, but Board contents only pins for I2C-0:

Python 3.12.3 (main, Feb  4 2025, 14:48:35) [GCC 13.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import board
>>> print(dir(board))
['CE0', 'D10', 'D11', 'D14', 'D15', 'D17', 'D18', 'D2', 'D22', 'D23', 'D24', 'D25', 'D27', 'D3', 'D4', 'D8', 'D9', 'I2C', 'MISO', 'MOSI', 'PWM1', 'SCK', 'SCL', 'SCLK', 'SDA', 'SPI', 'UART1_RX', 'UART1_TX', 'UART2_CTS', 'UART2_RTS', 'UART2_RX', 'UART2_TX', '__blinka__', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__repo__', '__spec__', '__version__', 'ap_board', 'board_id', 'detector', 'pin', 'sys']

 pip list
Package                                  Version
---------------------------------------- -------
Adafruit-Blinka                          8.56.0
adafruit-circuitpython-ahtx0             1.0.25
adafruit-circuitpython-busdevice         5.2.11
adafruit-circuitpython-connectionmanager 3.1.3
adafruit-circuitpython-register          1.10.2
adafruit-circuitpython-requests          4.1.10
adafruit-circuitpython-typing            1.11.2
Adafruit-PlatformDetect                  3.77.0
Adafruit-PureIO                          1.1.11
APScheduler                              3.11.0
binho-host-adapter                       0.1.6
blinker                                  1.9.0
board                                    1.0
click                                    8.1.8
Flask                                    3.1.0
gpiod                                    2.3.0
itsdangerous                             2.2.0
Jinja2                                   3.1.6
MarkupSafe                               3.0.2
parse                                    1.6.5
pathlib                                  1.0.1
pip                                      24.0
pyftdi                                   0.56.0
pyparser                                 1.0
pyparsing                                2.1.0
pyserial                                 3.5
pyusb                                    1.3.1
sysv_ipc                                 1.1.0
typing_extensions                        4.13.2
tzlocal                                  5.3.1
uWSGI                                    2.0.29
Werkzeug                                 3.1.3

Maybe board packed is not right!? How to install the right module?

[DvarfInkviz]

Solved my problem with Adafruit_Python_Extended_Bus