Hi there!
I believe the problem is a version mismatch between WPILib and the XRP firmware. WPILib 2024 Alpha 1 is intended to be used with at least firmware v0.5.x, the networking got an overhaul in this update that is not backwards compatible.
Once you get the firmware updated on the XRP, I’d recommend starting out with this WPILib example: GitHub - bb-frc-workshops/xrp-2024-alpha-example (Note, I believe you’ll need to change the IP address in line 64 of build.gradle to 192.168.42.1)
Also use v0.5.1 of the XRP firmware, v0.5.0 had a bug in it with the ultrasonic sensor: Release XRP-WPILib Firmware v0.5.1 · wpilibsuite/xrp-wpilib-firmware · GitHub
Please let us know how it goes, we’d love to hear any feedback you have!