RT1062 with MLX90640 - Failed to Init


I can use an external MLX90640 connected via i2c on the H7 (4.5.5) without any issues. However, on the RT1062 (4.5.5) running the same code the sensor is being detected Ok over i2c (I can see it on an i2c scan, and the fir.init() detects the sensor type Ok) but I get a “Failed to init the MLX90640” exception.

I’m checking for the sensor on the i2c bus as below, and can see it on both models of board :

#check we can see the sensor on 0x33 / 51
#Bus 1 on RT1062 2 on H7
bus = 1
i2c = machine.I2C(bus)  

and the exception on the RT1062 is thrown with a simple init


For info, have experimented with and without pull-ups on SDA + SCL

Has anyone else encountered this, or any thoughts?


Probably some type of bug.

The MLX90640 requires a repeated start on the I2C bus. This may have issues. I’ll make a bug tracker.

RT1062 I2C with MLX90640 not working · Issue #2229 · openmv/openmv (github.com)