Technic Hub Xbox controller discrepency?

[Artuchu]

I have two little bulldozer vehicles that are running the exact same code. The code lets them connect to an xbox controller and run around. However, one of them the code works perfectly fine. Connects to the controller and runs perfectly. The other one however crashes whenever it trys to connect the the controller. The xbox controller and the crashing vehicle are on the latest versions of their software. everythings connected to the correct ports. I've fully reset the vehicle and tried from there. I don't know what else I could be missing. any ideas would be greatly appreciated. Thank you!

Here's the code,

# ---ARTUCHU--- 4/24/26 3:27 AM
from pybricks.hubs import TechnicHub
from pybricks.iodevices import XboxController
from pybricks.parameters import Button, Color, Direction, Port
from pybricks.pupdevices import Motor,Light
from pybricks.tools import StopWatch,multitask,run_task,wait

# Set up all devices
technic_hub = TechnicHub()
xbox_controller = XboxController()
Left = Motor(Port.A, Direction.COUNTERCLOCKWISE)
Right = Motor(Port.B, Direction.CLOCKWISE)
light = Light(Port.D)

#Variables
islighton = 0
a_button_pressed_last_cycle = False
inactivity_timeout = 60000
min_voltage = 6500
max_voltage = 8400
technic_hub.light.on(Color.WHITE)
stopwatch = StopWatch()

async def handle_inputs(): #Movement
    global islighton, a_button_pressed_last_cycle
    while True:
        buttons = xbox_controller.buttons.pressed()
        triggers = xbox_controller.triggers()

        # Triger Forward
        if triggers[0] > 5 or triggers[1] > 5 or Button.RB in buttons or Button.LB in buttons:
            stopwatch.reset()
            left_speed = triggers[0]
            right_speed = triggers[1]
            if Button.LB in buttons: left_speed = -50
            if Button.RB in buttons: right_speed = -50
            if Button.LB in buttons and Button.B in buttons: left_speed = -100
            if Button.RB in buttons and Button.B in buttons: right_speed = -100
            Left.dc(left_speed)
            Right.dc(right_speed)

        # Left Joystick 
        elif any(abs(v) > 5 for v in xbox_controller.joystick_left()):
                    lx, ly = xbox_controller.joystick_left()
                    Left.dc(ly + lx)
                    Right.dc(ly - lx)
                    stopwatch.reset()

        # Right Joystick 
        elif any(abs(v) > 5 for v in xbox_controller.joystick_right()):
                    lx, ly = xbox_controller.joystick_right()
                    Left.dc(ly + lx)
                    Right.dc(ly - lx)
                    stopwatch.reset()

        else: #cleanup
            Left.stop()
            Right.stop()
        
        #A Button (Light Toggle)
        if Button.A in buttons:
            if not a_button_pressed_last_cycle:
                stopwatch.reset()
                if islighton == 0:
                    light.on(100)
                    islighton = 1 
                    a_button_pressed_last_cycle = True
                else:
                    light.off()
                    islighton = 0
                    a_button_pressed_last_cycle = True
        #Escape
        elif Button.LJ in buttons and Button.Y in buttons and Button.GUIDE in buttons:
            raise SystemExit
        else:
            a_button_pressed_last_cycle = False
        await wait(20)

async def monitor_system(): #everythting else
    global islighton
    while True:
        #Update battery
        voltage = technic_hub.battery.voltage()
        battery_percent = (voltage - min_voltage) * 100 / (max_voltage - min_voltage)
        if battery_percent < 10: #Low Battery Warning
            technic_hub.light.on(Color.RED)
            technic_hub.light.blink()
            light.on(100)
            await wait(300)
            light.off()
            await wait(300)
            light.on()
            await wait(300)
            light.off()
            await wait(1000)

        if stopwatch.time() > inactivity_timeout:
            Left.stop()
            Right.stop()
            light.off()
            islighton = 0
        await wait(100)

run_task(multitask(handle_inputs(), monitor_system()))

[BertLindeman]

Maybe a longshot, but are all objects on the correct port?
That would simply explain the situation.
To test that, you could move the line
xbox_controller = XboxController()
after the motor and light definitions.
That would eliminate one potential problem.

Another might be to write the potential exception to user storage, so you could look at it later.....

Bert

[Artuchu]

moved it down pass line 22 (technic_hub.light.on(Color.WHITE)) and the first time it turned white then didn't do anything then on the next activation it did the same crash again,

[dlech]

We've been doing frequent updates lately and have several release channels, so "latest" is not clear. Can you please give exact version numbers?

[Artuchu]

Version number for the code editing software is v3.6.1 (Pybricks Code v2.6.1). I can't find the firmware version number, however I did reinstall it around 4 hours ago now

[laurensvalk]

When you use the Xbox Controller with your other hub, remember to put the controller in paring mode again.

It will only remember the last one.

It's best to put the controller in pairing mode before you start the hub program, or it will attempt to the unpairable controller and fail.

[Artuchu]

Yep, sorry for wasting everyone's time, I genuinely forgot that Xbox controllers had the actual pairing button and not just the Xbox button. I should have just figured this out and not posted it lol, so sorry

[laurensvalk]

No worries! Newer controller models are a bit more forgiving. They let you turn it on with the pairing button, skipping the Xbox button completely. If you always use the pairing button that way, things will "just work" with either hub.