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Issue with PCA9548A Multiplexer and Multiple Sensors with Same Address

**Subject:** Issue with PCA9548A Multiplexer and Multiple Sensors with Same Address

I am working on a project where I use the PCA9548A multiplexer to read data from three MPU6050 sensors and five MLX90614 IR sensors. Both sets of sensors share the same I2C address. Despite implementing channel switching on the multiplexer, the sensor readings are not being distinguished properly. Instead, I am getting the same data across sensors with identical addresses, even though they are connected to different channels.

I have attempted the following troubleshooting steps:
1. Manually assigning each sensor to its respective multiplexer channel and explicitly ending the transmission after each channel selection.
2. Verifying the wiring, sensor integrity, and initialization sequences to ensure proper setup.

However, these measures have not resolved the issue. For the IR sensors (MLX90614), only the first sensor connected is read correctly, while the others appear “offline” or show the same value. This behavior persists regardless of the channel or physical connection used.

Additionally, I previously encountered a similar issue with the MLX90614 sensor, where the data from sensors on separate channels was not distinct. I suspect the issue may relate to how the multiplexer handles address conflicts or manages communication with sensors sharing the same address.

I would appreciate your guidance in resolving this issue or any insights into possible limitations of the PCA9548A with sensors sharing identical I2C addresses.

  1. Afuevu#0000

    Do you disable all previous channels before activating a new channel?
    The MLX90614 may need to be reset before reading again.
    You probably have verified the pull up resistors, but if not you can confirm it is present.
    Also ensure proper delays between comm intervals

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