Contributions:RHX
Synopsis
The Intan RHS has four SPI ports (with each port labelled A,B,C,D) which sends data to a FPGA. These ports communicate with the chips located on supported headstages. Each port has four output signals responsible for communication with the amplifier chips, two of which (MISO1,MISO2) are used to transmit data. Each chip controls 16 channels, and each chip transmits data over a single MISO line. Over all four ports, this means there are 8 lines over which data can be sent.
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RHS2116 Amplifier chip on 32 channel headstage
Attatched to the FPGA is an Opal Kelly XEM6010 USB/FPGA interface which can be used to read data in the FPGA via USB. This module has 128MByte SDRAM
Parameters
SamplingRate: Due to the RHS's ability to only take on discrete sampling rates, a value matching one of the following must be used for this parameter (given in Hz): 1000, 1250, 1500, 2000, 2500, 3000, 3333, 4000, 5000, 6250, 8000, 10000, 12500, 15000,20000 ,25000, 30000.
SampleBlockSize: The API provided by Intan only reads data in chunks of 128. Therefore, values that are multiples of 128 must be used for this parameter.
ConnectionType: Determines type of connection to be used. For devices with a XEM7310 module (which can be found via the connected device list given in the Intan RHX application or by looking at the specifications for the device in use), use ControllerStimRecord. Otherwise, depending on the USB connection, choose USB2 or USB3.
~To be added~
Trigger parameters:
TriggerEnable: enables or disables the trigger function
TriggerType: Edge triggered: triggers stimulation upon change from inactive to active state. Level triggered: repeats stimulation while in an active state (i.e. can activate multiple times while the trigger condition is met, without needing to switch)
TriggerState: Allows the user to enter a state that will be used as a trigger condition (i.e. can use KeyboardMonitor)
TriggerValue: The value in which TriggerCondition will be compared to.
TriggerCondition: The condition which TriggerState must satisfy in relation to TriggerValue in order to switch to an active state.
Pulse train parameters:
PulseTrainEnable: True: enables pulse train. False: sets stimulation to only a single pulse of the waveform.
PulseTrainNumPulses: Number of pulses to be executed upon trigger activation
PulseTrainPeriod: time elapsed between the start of two subsequent pulses (i.e. stimulus duration+interstimulus interval)
PostTriggerDelay: Time between trigger activation and execution of pulse train
RefractoryPeriod: Rest period after pulse train finishes executing during which stimulation will not execute
Waveform parameters: A1: Magnitude of first phase current (nA) A2: Magnitude of second phase current (nA) Polarity: Anodic: supplies positive current first. Cathodic: supplies negative current first D1: Duration of first phase D2: Duration of second phase DP: Interphase delay duration (Only applicable for Biphasic with Delay stimulation shape)
Shape: Biphasic: supplies current (with polarity determined by the Polarity parameter) for time determined by D1 and magnitude determined by A1, then supplies the opposite sign of current for time determined by D2 and magnitude determined by A2 Biphasic with delay: supplies current (with polarity determined by the Polarity parameter) for time determined by D1 and magnitude determined by A1, then supplies no current for time specified by DP, then supplies the opposite sign of current for time determined by D2 and magnitude determined by A2 Triphasic: supplies current (with polarity determined by the Polarity parameter) for time determined by D1 and magnitude determined by A1, then supplies the opposite sign of current for time determined by D2 and magnitude determined by A2, then repeats the first phase (current of initial polarity for duration D1 and amplitude A1)