Network Tables C++

Question

I am quite new to C++ socket programming. Since I am in an FRC team, I need to communicate between my application and the Compact RIO via an interface known as "Network Tables". I need to communicate from my C++ vision application to our robot code in Java. How do I implement NetworkTables in regular C++?

Answer 1

So here is what I did in python but the concept is the same. The goal would be to move motors based on values (sensor data) from what you receive in your driver station? so, how do I accomplish this... data transfers will be done through network tables

first, initlize...

from networktables import NetworkTables

# As a client to connect to a robot
NetworkTables.initialize(server='roborio-XXX-frc.local')

• creating the instance you will be able to access NetworkTables conections, configure settings, listeners and create table objects which is what is actually being used to send data

next,

sd = NetworkTables.getTable('SmartDashboard')

sd.putNumber('someNumber', 1234)
otherNumber = sd.getNumber('otherNumber')

Here, we're interacting with the SmartDashboard and calling two methods, to send and recieve values.

another example, from API docs

#!/usr/bin/env python3
#
# This is a NetworkTables server (eg, the robot or simulator side).
#
# On a real robot, you probably would create an instance of the
# wpilib.SmartDashboard object and use that instead -- but it's really
# just a passthru to the underlying NetworkTable object.
#
# When running, this will continue incrementing the value 'robotTime',
# and the value should be visible to networktables clients such as
# SmartDashboard. To view using the SmartDashboard, you can launch it
# like so:
#
#     SmartDashboard.jar ip 127.0.0.1
#

import time
from networktables import NetworkTables

# To see messages from networktables, you must setup logging
import logging

logging.basicConfig(level=logging.DEBUG)

NetworkTables.initialize()
sd = NetworkTables.getTable("SmartDashboard")

i = 0
while True:
    print("dsTime:", sd.getNumber("dsTime", -1))

    sd.putNumber("robotTime", i)
    time.sleep(1)
    i += 1