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i2c Raspberry pi4 with LCD Display not detected
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i2c Raspberry pi4 with LCD Display not detected

by loonhaunt on Thu Dec 02, 2021 2:39 pm

Hello,

I think a barbecued my i2c interface on my Rpi4. I spent hours trying figure out why I could not i2cdetect -y my LCD display, I had one other LCD display with the PCF 8574 chip on the backside and could not detect that either. So plugged the LCD into one of my rpi 3's and detected the at 00x27 just like it should. So my question is thus, is the issue with the rpi 4 hardware or some OS thing? ic2 smbus or whatever, and what can I do to determine if this is hard or soft issue?

Dave

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Re: i2c Raspberry pi4 with LCD Display not detected

by loonhaunt on Thu Dec 02, 2021 11:14 pm

I am posting to my own topic, but.... I have a Rpi 400 and Rpi 4 that I am unable to detect i2c bus anywhere?
Has anyone else had this this issue? I have full upgraded everything, and have the interface enabled for i2c

Appreciate the input in advance

Dave

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Posts: 81
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Location: Colorado US

Re: i2c Raspberry pi4 with LCD Display not detected

by rpiloverbd on Fri Dec 03, 2021 10:44 am

Have you checked the interfacing option? Most of the time it happens when the I2C interface is disabled.

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Re: i2c Raspberry pi4 with LCD Display not detected

by adafruit_support_carter on Fri Dec 03, 2021 5:22 pm

You do need to enable the I2C bus to have it show up. If you've done that and still are not seeing it - can you elaborate on what "unable to detect" means?

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