RoboRio w. LabView + daughterboard: configuring NetworkTables?

[lobrien]

How do you configure LabVIEW on the robot to communicate via NetworkTables with a daughterboard also on the robot?

The main drive team is using LabVIEW to program our robot. We are working on Computer Vision using python on a daughterboard (Jetson, hopefully). Our challenge is that to control the servos on the targeting subsystem, our understanding is that we cannot do that with GPIO/I2C from the Jetson but need to go back through the main PD board, which is controlled by the RoboRio.

OK, so the hope is to use NetworkTables for communication. We have pynetworktables up and running and we can communicate between a Python client and a Python server. I know _ZERO_ about LabVIEW.

Which is the NetworkTables server? The RoboRIO or the daughterboard?

One way or the other, how do we configure LabVIEW to use NetworkTables? If it's the server, how do we access tables and key-values being manipulated by the daughterboard? If it's the client, we additionally need to know how to set the IP address of the server running on the daughterboard.

Thanks in advance!

[virtuald]

The Robot is the server. LabVIEW has a networktables library, though I don't know how it works. Search the forums and I'm sure you'll find some answers.

The RobotPy documentation site has some language-agnostic docs explaining networktables that you might be interested in: http://robotpy.readthedocs.io/en/stable/guide/nt.html

[Jonathan L.]

The attached shows how to Write or Read a Network Table Variable in LabVIEW from the roboRIO or Dashboard code.

A list of active Network Table Variables is displayed on the LabVIEW Dashboard by default.

Originally Posted by lobrien

Our challenge is that to control the servos on the targeting subsystem, our understanding is that we cannot do that with GPIO/I2C from the Jetson but need to go back through the main PD board, which is controlled by the RoboRio.

The Power Distribution Panel is only a sensor of current; it is NOT controlled by anything. To use a motor you must use a motor controller. Or to use a servo (at least a normal one) you connect it to a PWM port on the roboRIO.

R73 restricts actuators from being controlled by anything else than the roboRIO as you said.