Acq Board Output#

Annotated settings interface for the Acq Board Output plugin
Triggers digital outputs of an Open Ephys acquisition board with an Opal Kelly FPGA.#

Plugin Type



Windows, Linux, macOS

Built in?

No; install via Rhythm Plugins

Key Developers

Josh Siegle, Aarón Cuevas López

Source Code



For more in-depth documentation on the Open Ephys Acquisition Board, please refer to the Acquisition Board docs site.


If your acquisition board was purchased after October 2022, it likely has a custom FPGA designed by Open Ephys. This requires a different plugin, called OE FPGA Acquisition Board, which doesn’t currently have an associated output plugin.

Installing and upgrading#

The Acq Board Output plugin is not included by default in the Open Ephys GUI. To install, use ctrl-P or ⌘P to open the Plugin Installer, browse to the “Rhythm Plugins”, and click the “Install” button. After installation, Acq Board Output will appear in the processor list on the left side of the GUI’s main window.

The Plugin Installer also allows you to upgrade to the latest version of this plugin, if it’s already installed. The plugin must be removed from the signal chain prior to upgrading.

Plugin configuration#

If this plugin is placed downstream of the Acquisition Board plugin, as well as a plugin that generates TTL events (e.g., Crossing Detector or Ripple Detector), the digital output channel specified by the TTL_OUT parameter will be temporarily set to high each time a TTL event is received on the TRIGGER_LINE. The approximate duration of this event (in milliseconds) is set by the EVENT_DURATION parameter.

This configuration can be used to perform closed-loop feedback experiments in which some feature of the neural data (such as phase of an oscillation, or the presence of a ripple event), is used to trigger stimulation.

Because the board will also be acquiring data, response times may be longer than when using a dedicated piece of hardware for generating outputs. If faster feedback is required, we recommend using the Arduino Output or Pulse Pal plugins instead.