# Connecting a Cedrus Riponda (RB-x40) Response Box in PsychoPy – Working Setup + Common Errors

**URL:** <https://discourse.psychopy.org/t/connecting-a-cedrus-riponda-rb-x40-response-box-in-psychopy-working-setup-common-errors/46657>\
**Category:** Builder\
**Tags:** forum\
**Created:** [February 24, 2026, 1:03pm UTC](https://discourse.psychopy.org/t/connecting-a-cedrus-riponda-rb-x40-response-box-in-psychopy-working-setup-common-errors/46657 "2026-02-24T13:03:55Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Martina\_Seveso](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/martina_seveso/32/33529_2.png) [@Martina\_Seveso](https://discourse.psychopy.org/u/Martina_Seveso)\
**Post date:** [February 24, 2026, 1:03pm UTC](https://discourse.psychopy.org/t/connecting-a-cedrus-riponda-rb-x40-response-box-in-psychopy-working-setup-common-errors/46657/1 "2026-02-24T13:03:55Z")

</div>

Hi everyone,

I’m posting the full setup steps that worked for connecting a **Cedrus Riponda (RB-x40) response box** in PsychoPy, along with some version-related issues and fixes I encountered when moving to another desktop. I hope this might help anyone having issues with this process

Working Configuration: **PsychoPy version:** 2025.2.4

# Riponda (Cedrus) Response Box Setup in PsychoPy

Install Xidron + Drivers

- Install **Xidron software -** [https://cedrus.com/support/riponda/update-firmware.htm](https://cedrus.com/support/riponda/update-firmware.htm)
- Install the **Cedrus drivers-** [https://cedrus.com/support/riponda/index.htm](https://cedrus.com/support/riponda/index.htm)
- Restart your computer after installation.

Install the Cedrus Package in PsychoPy

- Open PsychoPy \>\>Switch to **Coder view \>\>** Paste and run:

```auto
from psychopy.tools import pkgtools
pkgtools.installPackage('psychopy-cedrus')

```

- It may take a while. If it doesn’t run cleanly, close and reopen PsychoPy. Restart PsychoPy completely after installation.

#### Add the Cedrus Device in Builder

Open your experiment in \*\*Builder view \>\> Click **Experiment Settings** (gear icon) \>\> Go to **Devices** \>\> Click **Add Device** \>\> Select **Cedrus RB-x40 / XID device** \>\> Name the device (e.g., `ripondaRB`) \>\> Under **Keys allowed** , enter the button numbers you want to use \>\> Save

#### Disable the Keyboard

Remove any **Keyboard components** from routines OR Ensure no keyboard responses are being recorded. Only the Cedrus device should collect responses.

#### Test the Box

Open **Xidron** to confirm button presses are detected \>\> Run a short PsychoPy test trial \>\> \* Confirm buttons register correctly

# Issues Encountered on Another Desktop

When testing on a different computer, I encountered version-related errors.

## Error 1 (PsychoPy 2026)

```auto
...psychopy_cedrus\components\util.py", line 55, in writeXidButtonBoxCode
buff.writeOnceIndentedLines(code % inits)
KeyError: 'deviceLabel'

```

_Possible Solution_: Downgrade to **PsychoPy 2025.2.4**

## Error 2 (PsychoPy 2025.2.3)

```auto
...psychopy\experiment\devices.py", line 203, in applyJSON
self.params[name].applyJSON(val)
KeyError: 'name'

```

_Possible Solution_: Delete the `devices.json` file located at: C:\Users\YOURNAME\AppData\Roaming\psychopy3. Restart PsychoPy after deleting.

## Error 3 (PsychoPy 2025.2.4 – Opening Device Manager)

```auto
...psychopy\preferences\devices.py", line 62, in load
val['cls'].split(".")[:-1]
KeyError: 'cls'

```

_Possible Solution_: delete C:\Users\YOURNAME\AppData\Roaming\psychopy3\devices.json . Restart PsychoPy.