I’m a software mentor with a FIRST robotics team. We purchased the v3 but are having trouble communicating with it from the RoboRIO. In the user guide, I found generic wiring and i2c register information. I was able to communicate with the v3 using an Arduino for testing (using the provided Arduino library on GitHub), but we’re unable to get it working with the RoboRIO (using Java WPILIB). Does anyone have any FRC/RoboRIO specific information to help us?
If you were able to get it working with an Arduino, the sensor itself is functional, and you know how to use it, so it’s a nuance with the roboRIO or the programming. The roboRIO is not something we carry, so cannot provide much insight. Perhaps a member of the community might have some insight?
We had a reply from the manufacturer:
I believe the unit may be defective. The unit which previously worked with the arduino sample code no longer works with it. I purchased one Lidar Lite v3 myself, and our robotics team purchased 3 more, so I have 4 identical units available to test with. To eliminate the roborio and our user code from the equation, I am now testing with a raspberry pi and using the i2c-tools to scan the i2c bus and read values from them.
Out of the 4 units at our shop, 2 of them are not working. These 2 units do not show up on the i2c bus at all. I am using the same wiring harness between tests so I know the connections are ok. Using the command “i2cdetect -y 1”, when one of the non-working ones is connected, shows no i2c addresses found (all addresses show – placeholder). However, with a working unit connected, i2cdetect correctly shows the 0x62 address, and subsequent calls to “i2cdump -y 1 0x62” shows valid register contents.
Is it possible that the 2 problematic units have simply failed? Or is it possible that our electrical team may have damaged them while wiring them? Although they are high school students, they also wire a variety of other motors, sensors, displays, etc without any problems on a regular basis… so it seems unlikely to me that they would have damaged two of them already… unless there is something particularly fragile about the Lidar Lite v3 which would make it more susceptible to damage (?). (Note none of these have been attached to an actual robot, so they have NOT been banged up or exposed to any physical abuse).
Or is it possible that something in the Lidar Lite memory has been corrupted or overwritten and would need to be reset? Any suggestions for how to reset it? (I see in the manual you can reset all default register values using i2c, but that doesn’t help me since it won’t respond to i2c).
Thank you,
Randy Brown
Software Mentor
FRC Team #3966
We have reached out to the manufacturer and they will either reply here or will pass along their suggestions.
Please send an e-mail to [email protected] with your order or invoice number and we will replace the two defective units.
Randy I sent a copy of our code for the Lidar Lite v3 to Roborio to your team president email. It is in Java.
I tried to post it here but I keep getting a Server error when I do.
Hope it helps. Good luck this year.
Carlos Reckner
Mentor
CyberSonics
FRC Team #103