Contributions:MicroLeadsADC

Introduction

CortecADC is a source module that allows for inter-cranial recording and stimulating over 32 channels via a fully implantable device. It is intended for long-term measurement of neural activity and electrical stimulation of brain tissue. See the CorTec site for more information.

Versioning

Authors

Dhruva Mehta (mehta@neurotechcenter.org)

Version History

2/10/2023 Initial Creation and Setup

Source Code Revisions

Initial development:
Tested under:
Known to compile under:
Broken since: --

Known Issues

Parameters

SourceCh

The total number of digitized and stored channels. Because of device limitations, this is set to 4 channels explicitly.

SampleBlockSize

Samples per channel per digitized block. Together with the sampling rate, this parameter determines how often per second data are collected, processed, and feedback is updated. For example, at 1000 Hz sampling and a SampleBlockSize of 20, the system (e.g., source signal display, signal processing, and stimulus presentation) will be updated 50 times per second.

SamplingRate

The sample rate of the system. This parameter cannot be edited, and will default to the sampling rate available from the implant which is 21500 Hz. In case you are experiencing problems by higher sampling rates (e.g., data loss, jerky display, etc.), increase the SampleBlockSize so that you are updating the system less frequently (usually, updating the system 20-30 times per second is sufficient for most applications), and increase Visualize->VisualizeSourceDecimation. This parameter will decrease the number of samples per second that are actually drawn in the Source display.

SourceChOffset

Offset for each channel.

SourceChGain

Gain for each channel.

ChannelNames

Names of each channel.

ReferenceCh

This list defines what channels will be used as reference. This list is uploaded to the device and set in hardware, effecting the raw bio-signal data that is recorded by BCI2000. If you do not want to effect the raw bio-signal data that is recorded, you can use the spatial filter. If this parameter is set to auto, no reference channels are used.

Stimulation Parameters

These parameters can be found in the "Stimulation" tab of the BCI2000 config window.

Enable STIM0

This parameter enables/disables stimulation for the STIM0 channel.

Enable STIM1

This parameter enables/disables stimulation for the STIM1 channel.

Enable Recording

This parameter enables/disables streaming of neural data.

Supply Voltage

This parameter sets the supply voltage from a range of 4V to 9V. When the user is recording only, the voltage must be 4V. When the user is stimulating at all, the voltage must be 9V.

Stimulation Pulse Settings

Phase1 Duration

This parameter sets the length of the Phase 1 Duration in counts of 11.6 microseconds. To obtain the proper value, divide your duration by 11.6 microseconds.

Interphase Duration

This parameter sets the length of the Interphase Duration in counts of 11.6 microseconds. To obtain the proper value, divide your duration by 11.6 microseconds.

Phase2 Duration

This parameter sets the length of the Phase 2 Duration in counts of 11.6 microseconds. To obtain the proper value, divide your duration by 11.6 microseconds.

Phase1 STIM0 Amplitude counts

This parameter sets the Phase 1 amplitude for the STIM0 channel in counts of 10 microAmps. To obtain the proper value, divide your amplitude by 10 microAmps.

Phase1 STIM1 Amplitude counts

This parameter sets the Phase 1 amplitude for the STIM1 channel in counts of 10 microAmps. To obtain the proper value, divide your amplitude by 10 microAmps.

Phase2 STIM0 Amplitude count

This parameter sets the Phase 2 amplitude for the STIM0 channel in counts of 10 microAmps. To obtain the proper value, divide your amplitude by 10 microAmps.

Phase2 STIM1 Amplitude count

This parameter sets the Phase 2 amplitude for the STIM1 channel in counts of 10 microAmps. To obtain the proper value, divide your amplitude by 10 microAmps.

Charge Recovery Counts

This parameter sets the length of the Charge Recovery Duration in counts of 11.6 microseconds. To obtain the proper value, divide your duration by 11.6 microseconds.

Stim Period Counts

This parameter sets the length of the Stim Period Duation in counts of 11.6 microseconds. To obtain the proper value, divide your duration by 11.6 microseconds.

ADC Gain

This parameter sets the ADC Gain. When recording only, set the parameter to 0. When stimulating, set the parameter to 1.

Exfil_Iface

This parameter sets the exfil settings. When recording only, set the parameter to 2. When stimulating, set the parameter to 0.