guineawheek / halsim_socketcan

HALSIM_SocketCAN

This binds SocketCAN listeners to HALSIM CAN functions. As SocketCAN is Linux only, this vendordep only functions on Linux platforms that are in simulation mode. Supports both Java and C++.

Applications:

• Hardware attached integration testing with CAN devices
• using WPILib on something that's not a roboRIO
• using real CAN with a Romi or something similar (may require additional work)

Building/Installing

1. copy HALSIM_SocketCAN.json to your project's vendordep json folder

2. run

# Feel free to change 2023 to the correct year
./gradlew publishToMavenLocal && cp -r ~/.m2/repository/halsim ~/wpilib/2023/maven

in this repo

Eventually there will be a proper maven sever...hopefully.

General running tips

FRC non-FD buses (that is, everything except the CANivore) uses 1 Mbps CAN so to configure a SocketCAN interface on can0 one might do:

sudo ip link set can0 type can bitrate 1000000 && sudo ip link set can0 up

to provision can0

Running in C++

Assuming the SocketCAN interface is can0 -- consult your local ip link to be sure.

#include <HALSIM_SocketCAN.h>

int main() {
  // make sure that CAN-using objects are not instantiated first via static fields
  HAL_Initialize(500, 0);
  HALSIM_SocketCAN_Enable("can0");
  return frc::StartRobot<Robot>();
}

Running in Java

import halsim.socketcan.HALSIM_SocketCAN;

// edit your Main.java as such:

public static void main(String... args) {
if (!HAL.initialize(500, 0)) {
    throw new IllegalStateException("Failed to initialize. Terminating");
}
HALSIM_SocketCAN.enable("can0");
RobotBase.startRobot(Robot::new);
}

Building and editing this vendordep

This uses gradle, and uses the same base setup as a standard GradleRIO robot project. This means you build with ./gradlew build, and can install the native toolchain with ./gradlew installRoboRIOToolchain. If you open this project in VS Code with the wpilib extension installed, you will get intellisense set up for both C++ and Java.

By default, this template builds against the latest WPILib development build. To build against the last WPILib tagged release, build with ./gradlew build -PreleaseMode.