.. _userDevicesMockClamp:

Simulated Patch Clamp Amplifier
================================

For demonstration and testing purposes, ACQ4 includes a device that simulates the behavior of a patch clamp amplifier attached to a neuron. To use this device, it is necessary to also define a :ref:'NiDAQ device <userDevicesNiDAQ>' that has the configuration parameter ``mock: True``  (it is not necessary to have a physical DAQ device). This device may be used to test the :ref:`Patch <userModulesPatch>` and :ref:`TaskRunner <userModulesTaskRunner>` modules.

Internally, the neuron and electrode are simulated with a simple Python script (located at acq4/devices/MockClamp/hhSim.py). This script defines a basic Hodgkin-Huxley neuron and a patch electrode with access resistance. 


Configuration Options
---------------------

Example configuration:


::
    
    Clamp1:
        driver: 'MockClamp'
        simulator: 'builtin'  # Also supports 'neuron' if you have neuron+python
                              # installed. See lib/devices/MockClamp/neuronSim.py.
                            
        # Define two connections to the DAQ:
        Command:
            device: 'DAQ'
            channel: '/Dev1/ao0'
            type: 'ao'
        ScaledSignal:
            device: 'DAQ'
            channel: '/Dev1/ai5'
            mode: 'NRSE'
            type: 'ai'
            
        # Default holding values.
        icHolding: 0.0
        vcHolding: -50e-3
  

.. Manager Interface
.. -----------------



Task Runner Interface
---------------------

The task runner interface for the MockClamp is similar to the interfaces defined for :ref:`AxoPatch <userDevicesAxoPatch>` and :ref:`MultiClamp <userDevicesMultiClamp>` devices.

    .. figure:: images/MockClamp_TaskInterface.png
    
The left half of this interface consists of three main sections:
    
* A list of operating modes (vc, i=0, ic). The selected clamp mode will be set immediately before the task is executed.
* Controls affecting recording from the primary output channel of the amplifier (Scaled Signal). 
* Controls that determine the command output:
    * **Pre-set** sets the voltage or current command immediately before the task begins, if the box is checked.
    * **Holding** determines the voltage or current command that will be set immediately *after* the task finishes. If the box is unchecked, then the current holding value (as indicated in the Manager interface described above) will be used.
    * A :ref:`function generator <userInterfacesFunctionGenerator>` that is used to specify the output waveform and sequence parameters.

The right half of the interface holds :ref:`plot areas <userInterfacesGraphics>` for displaying the recorded signal (top) and command signal (bottom).