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I2C Level Converter with Bar30 Pressure Sensor


Hey Jacob, looks like soldering it did the trick although altitude readings look a bit off. I imagine this could be due to the sensor being designed to work underwater and not it air?

If not, I assume this will not be a problem as I can just do some calibrations.

Thanks again, great customer support! :slight_smile:

(Jacob) #43

@Owen Atmospheric variation can offset the pressure reading by up to a few decimeters. Yes, you will need to calibrate it by subtracting this offset to ‘zero’ or ‘tare’ the reading. This is what we do in the ArduSub software on our ROVs.

We do test every sensor, it is possible (but not likely) that one was missed or malfunctioning. @pam, Can you please carefully double check all of the points made in this thread? I think that you are experiencing the same issue as @Owen, and that if you were to solder the green wires (or use new crimped jumpers), it will work.

(pam) #44

I just double checked all you said as well as continuity of all elements. I believe, I have done them correctly, but it is still not working.
Is each of the pins of right side of the board supposed to have continuity with the corresponding pin of left side of the board? (are the same pins of the left and right side of the board (Host Device and Sensor pins) supposed to have continuity?). Because, if this is the case, the pins of SCL of right side and left side do not have continuity (they are not connected to each other) and neither SDA pins of right and left of the board are connected.



(Adam) #45

Hi Pam,

The power and ground pins will have continuity with each other when tested with a multimeter, but the SDA and SCL pins will not. This normal, and it due to these traces passing through the I2C level shifter component which does not behave like a simple point of continuity.

I have sometimes found that a breadboard can be the cause of certain mystery issues, they tend to wear down over time and can cause bad connections. It also appears as though you have soldered the pins such that the side going to the breadboard is shorter than normal, they may not be making proper contact. The plastic spacer should normally be on the side that will be mating- I know it doesn’t seem significant, but this could be a problem given sensitivity of I2C. I recommend trying an alternative connection method without a breadboard if possible.


(pam) #46


I took your last advise as well. I connected them with a proper f/m jumper wire without any bread board. But, it is still not working.

Please, let me know how I can return it to you or whether you can fix the issue if I send it to you.


(Jacob) #47


Can you please send an email to support@bluerobotics.com referencing this issue, and we will sort everything out to your satisfaction.


(pam) #48


Thanks for your great customer support.