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sparkfun / SparkFun_MLX90640_Arduino_Example

Controlling and reading from the MLX90640 IR array thermal imaging sensor
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Sparkfun MLX90640 i2c address issue #26

Open frank984 opened 1 year ago

frank984 commented 1 year ago

I connected two Sparkfun IR arrays to a Raspberry Pi 3a+ using a PCA9548A multiplexer: image Sometimes the code used read the IP of the sensors correctly: image Sometimes not, with the following string: image

The same thing happens when I use only a module connected directly to the Raspberry, without the multiplexer: without any variations hw or sw, sometimes the i2C address of the module is read correctly, sometimes not How can I solve the problem?

TurnerRussell50 commented 1 year ago

it's the i2c pullup jumpers; cut one of the sensors' traces on the board rear like so https://learn.sparkfun.com/tutorials/qwiic-ir-array-mlx90640-hookup-guide?_ga=2.150089077.238313185.1666643760-1841065663.1665480869&_gac=1.149695044.1665786185.CjwKCAjwkaSaBhA4EiwALBgQaA0DWIJgJYLZ5bEYuxxY6utz93O-6RlGy3eIyQJ-uKGoKDj382tI1xoCH9UQAvD_BwE#hardware-overview (leave one set intact)

frank984 commented 1 year ago

Even if I cut off all the extra sensors' I2c pullup jumpers, the modules do not have a '0x33' address. I solved the problem by desoldering the mlx90640 from the board: image Now the three sensors have the same '0x33' address: image