Contributions:g.EstimSwitchingUnit
Location
http://www.bci2000.org/svn/trunk/src/private/SignalProcessing/g.EstimSwitchingUnit
Versioning
Author
Alexander Belsten (belsten@neurotechcenter.org)
Version History
- 2020/05/22: Initial release for the switching unit prototype
Source Code Revisions
- Initial development: 6125
- Known to compile under: 6177
- Broken since: --
Functional Description
The purpose of this device and filter is to automate the process of switching channels from recording to stimulation during cortical stimulation experiments. Previously, channels had to be switched manually (unplugging electrodes from the amplifier and plugging them into a stimulator). With the switching unit and this filter, this process is automated.The filter has been developed using:
g.Estim Pro Switching Unit Prototype
Serial Number: SR-2019.10.01
API Version: 0.1.0537
Integration into BCI2000
Compile the filter by enabling BUILD_PRIVATE in your CMake configuration. Access to the private directory in the SVN is necessary.
Parameters
The g.EstimSwitchingUnit is configured in the filtering tab. The configurable parameters are:
EnableSU
This parameter enables the switching unit.
DeviceID
Index of the device on the system. If one switching unit is plugged into the computer this value should be 0.
Trigger
There are two options for the trigger, a software trigger, and a digital trigger.
Software Trigger
Channel switching is triggered when the StimulusCode state meets the stimulus condition defined in the first row of the StimConfig parameter. Note: if only one state (one column) is defined in StimConfig, channel information configuration will not need to be re-uploaded to the device. This results in a dramatic decrease in latency of transition between recording to stimulating. See the latency section for more details.
Digital Trigger
Channel switching is triggered by digital input on the back of the device, allowing for the use of foot pedals or push buttons. Only one state (one column) can be defined in the StimConfig parameter to use the digital trigger. When the digital trigger occurs, the switching configuration for that one state will be applied.
StimConfig
This matrix configures channel routing. The first row labeled by SwitchExpression is the channel routing condition. When SwitchExpression evaluates true, the channels will be routed for stimulation. The Stim+ ch and Stim- ch nested lists define what channels should be routed to the positive side (anode) of the stimulation input and to the negative side (cathode) of stimulation input.
Latency
Under construction... Check back soon!