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UM5S - I2C fail - LM75B not responding - where is it ?

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Posted · UM5S - I2C fail - LM75B not responding - where is it ?



Got some ER35/I2C Error.


Looking at https://support.ultimaker.com/hc/en-us/articles/360011575200, it could be in the feeder or more likely in the print head.


As an electronic engineer, I could say that I2C bus should be ONLY used for intra-card communication and should NEVER be used to communicate with remote devices, especially in area with motors... There is plenty of low cost solution available : differential TTL, RS232/485, or best CAN bus.


According to the boot log I have a problem with the LM75B (temperature sensor). Where is it?


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    Posted · UM5S - I2C fail - LM75B not responding - where is it ?

    Have you followed the linked support article? I had an issue once because the cable of a feeder wasn’t properly connected (or probably came loose during transport or vibrations during use) what led to highjacking the whole printer and giving a motion system error. After reseating the cable everything worked fine (and still does). I guess everything is connected to the same I2C bus, so a loose connector could easily corrupt the whole bus. It gave me a bit of a hint for a while before because it randomly threw feeder errors  (making me disable the filament sensors). 

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