Table of Contents

Control Poke Peripheral

The Mice Poke is a specialized nose poke peripheral for the Behavior board which combines an infrared beam sensor for poke detection, cue LEDs, and a solenoid valve for reward delivery. Refer to the connections article to set up the hardware connection on poke port P0, which we will use for the rest of these examples.

This article covers how to visualize poke events, debounce noisy inputs, drive the cue LED, and deliver rewards with the Mice Poke peripheral in Bonsai.

The complete workflow is shown below:

Detect Pokes

Note

You can use the Breakout extension board to adapt the poke ports as regular digital input/output pins to interface with other external devices or accessories.

Visualize Poke Events

Beam breaks in the Mice Poke peripheral are reported as digital input events. The three poke ports P0 - P2 are represented as DIPort0 - DIPort2 in the digital input DigitalInputState event register.

Detect Pokes Visualize Events

  • Insert a SubscribeSubject operator named Behavior Events. This will listen to HarpMessages broadcast from the PublishSubject named Behavior Events in the Harp device pattern.
  • Insert a Parse operator and configure the Register property to Timestamped<DigitalInputState>.
  • Insert a VisualizerWindow operator. This will automatically open a window displaying the parsed events when the workflow starts.

Run the workflow and block the infrared beam on the Mice Poke peripheral. The visualizer will display:

DIPort0@3.213504
None@3.513823

The first value is the payload, listing the digital inputs that are currently active, and the second value is the timestamp on the device clock. Both beam breaks and beam restores generate an event, so None marks the moment the poke was exited.

Configure Input Filter

A single poke can generate a burst of rapid transitions, for example, when the snout hovers at the edge of the infrared beam. The PokeInputFilter register sets a refractory period, in milliseconds. After each reported transition, further transitions on that port are ignored for the set time, so one poke reads as one entry and one exit.

Detect Pokes Input Filter

  • Insert a KeyDown operator and set the Filter property to A.
  • Insert a CreateMessage operator and configure the following properties:
    • Payload - Select PokeInputFilterPayload.
    • PokeInputFilter - Set the filter time to 5 ms.
  • Insert a MulticastSubject operator named Behavior Commands.

Run the workflow and press A — rapid repeated transitions within 5 ms of a poke event no longer generate events. Set the value to 0 to disable the filter. The default filter time is 1 ms.

Tip

The filter is blind to the cause of a transition, so values much longer than the animal's fastest re-entry will also ignore genuine consecutive pokes.

Drive the Poke LED

Each poke port carries an LED drive line (DOPort0 - DOPort2). The LED is controlled like any other digital output. For instance, you can turn it on and off with the OutputSet and OutputClear registers:

Detect Pokes Drive LED

  • Insert a KeyDown operator and set the Filter property to S.
  • Insert a CreateMessage operator and configure the following properties:
    • Payload - Select OutputSetPayload.
    • OutputSet - Select DOPort0.
  • Insert a MulticastSubject operator named Behavior Commands.

In a separate branch:

  • Insert a KeyDown operator and set the Filter property to D.
  • Insert a CreateMessage operator and configure the following properties:
    • Payload - Select OutputClearPayload.
    • OutputClear - Select DOPort0.
  • Insert a MulticastSubject operator named Behavior Commands.

Run the workflow, then press S to turn the P0 poke LED on and D to turn it off. See Control Digital Outputs for other methods to control the LED.

Deliver Rewards on Poke

Each poke port carries a 12 V valve drive line for a solenoid valve that gates reward delivery. The valve outputs (SupplyPort0–SupplyPort2) boot with pulse mode already enabled. The workflow below configures the pulse duration, then closes the loop in Bonsai where every poke at P0 immediately triggers a reward at the same port. The reward volume is calibrated by adjusting the pulse duration.

Detect Pokes Deliver Rewards

  • Insert a KeyDown operator and set the Filter property to F.
  • Insert a CreateMessage operator and configure the following properties:
    • Payload - Select PulseSupplyPort0Payload.
    • PulseSupplyPort0 - Set the valve opening duration in ms (e.g. 15, the boot default).
  • Insert a MulticastSubject operator named Behavior Commands.

In a separate branch:

  • Insert a SubscribeSubject operator named Behavior Events.
  • Insert a Parse operator and configure the Register property to DigitalInputState.
  • Insert a HasFlag operator and set the Value property to DIPort0.
  • Insert a Condition operator, leaving its inner workflow at the default. Only beam-break events at P0 pass through; beam restores and events from other ports are filtered out.
  • Insert a CreateMessage operator and configure the following properties:
    • Payload - Select OutputSetPayload.
    • OutputSet - Select SupplyPort0.
  • Insert a MulticastSubject operator named Behavior Commands.

Run the workflow, press F once to set the pulse duration, then block the infrared beam on the P0 poke. The valve will opens for 15 ms and close on its own, delivering one reward per poke.


Last updated with:
Hardware v2.1
Firmware v3.3
Bonsai Package v0.2

Edit this page