Rev Hardware Client

Success Criteria

  • Run a motor using
  • Plot the motor's position over time
  • Configure a motor's ID and basic settings
  • View an absolute encoder's output

Introduction to the Hardware CLient

https://docs.revrobotics.com/rev-hardware-client/gs/navigation

Configuring a Spark

https://docs.revrobotics.com/rev-hardware-client/ion/spark-max

Identifying a motor ID

  • Plug in your computer into any available Spark controller. The one you're interested is easier.
  • If you don't see anything useful, click "Scan For Devices" down in the bottom left
  • You should see one (or more!) devices in the left side.
  • Select the device that looks like your motor
  • Click the "Blink" button, and look at your physical hardware. The light should be flickering
  • If not, repeat this process until you find it.
  • You can see the Device ID in the device settings, and put that in your code.

Rev Reference Snippets

Config import warning!

Watch your imports when setting up Spark Configs. If you're not mindful, VSCode will pull in
import com.revrobotics.servohub.ServoHub.ResetMode;
instead of the desired
import com.revrobotics.spark.SparkBase.ResetMode;
This shows up as a error on your line for
motor.config(....);

Configuration Parameters
java
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motor.configure(
	config, 
	//This determines if we reset all existing parameters. 
	//Generally, we always want this on initialization, and then 
	//Manually set the values we expect to see for the robot.
	//The typical case for kNoResetSafeParameters is when we
	//change configuration after bootup. Changing Coast/Brake mode
	//is a common example.
	ResetMode.kResetSafeParameters, 
	
	//This option determines whether this config's settings
	//are saved on the Spark when it reboots.
	//In most cases, this doesn't matter, since the robot code
	//and Spark usually boot at the same time. However, in competition,
	//there's cases where a spark might lose power and reboot by itself!
	//Because of this, you usually want to set it to kPersistParameters,
	//but there's certain cases where kNoPersistParameters is preferable,
	//typically when it relates to increasing output power after validating
	//the system state.
	PersistMode.kPersistParameters
);