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By marikka

I've connected the SEN-14844 (MLX90640 IR Array) with the CAB-14988 cable:
Pin 1 (3.3V) - RED
Pin 3 (SDA) - BLUE
Pin 5 (SCL) - YELLOW

I confirmed each connection with a multimeter.
The red power led on the sensor board is on.
I've turned on /dev/i2c-1 using raspi-config.

When I run i2cdetect -y 1, I don't detect any device on the bus. I'm expecting to detect the device at 0x33.

What can I do to further debug the device? Should I expect the device to work with a raspberry pi 3B+?

Thank you!
Hi there,

Any luck with your mlx90640?

I just received the same breakout board from a third party distributor (I’m in Canada) and out of the packaging I had the same result - running i2cdetect -y 1 on my raspberry pi would not return any I2C addresses - even the other device on the I2C bus which had been found moments before. Turns out SCL was short circuited to ground when I check the device with my ohmmeter. The distributor sent me a replacement with similar results. This time however SDA is shorted to ground and when I run i2cdetect -y 1 it returns ALL of the possible I2C device addresses. Once I remove the mlx90640 I can again detect my other connected devices. Seems there is a quality control issue with that particular batch of sensors as a friend ordered the same sensor from the same distributor at the same time as has had similar problems.

I have already tried this sensor with Raspberry Pi 3 models, but unfortunately it is not compatible with Raspberry Pi's (or I should say Broadcom's) I2C hardware bug.

I spent a lot of time trying many different things, but there is just some things the raspberry PIs are not able to communicate to over I2C (Something about not able to adapt to clock stretching).

Would have been the perfect controller to work with this camera too! PCDuino does not have this issue however, which I confirmed with same I2C-dev library does communicate to the sensor reliably.