Continuously Sampled Acquisition Entity Properties


These settings are used to control how the CSC/CSG acquisition entities process AD data and what it does with the data after processing.  The acquisition entity (AE) settings are shown on the properties page when a time plot or CSC/CSG AE is selected in the properties tree.


CSC/CSG Acquisition Entity Settings




CSC/CSG Acquisition Entity General Settings

1. Acquisition Entity Name This is the unique name that is used to identify this acquisition entity.  It is the name you chose when you created the acquisition entity in the configuration file.
2. Sub System Name This is the name of the recording system from where this acquisition entity will receive its data.  By default, the __lynxsx_hardware_name System is always named AcqSystem1
3. Sampling Frequency This is the rate at which __prod_name is sampling data for this acquisition entity.
4. A/D Channel Number This is the AD channel on the acquisition subsystem where data is obtained for this CSC/CSG acquisition entity.
5. Sub Sampling Interleave This command allows you to record data for a particular acquisition entity at a lower sampling rate than other acquisition entities.  The sub sampling interleave tells __prod_name to process only every Nth (where N is the Value specified) sample obtained from the recording hardware.  This can also be seen as a sampling divisor. This setting cannot be changed while __prod_name is recording or acquiring.

The value must be between 1 and 128 for CSC/CSG acquisition entities.

Example:  An __lynxsx_hardware_name Acquisition Amplifier system samples all channels at 32000 Hz.  If you want to sample CSC1 at 8000 Hz.  You would type 4 in the box and hit enter. This will only process every 4th sample, giving an effective sampling rate of 8000 Hz for the selected CSC.  Multiple CSC/CSG entities can be updated with a global selection.
6. Input Inversion Setting __prod_name will automatically invert incoming AD data before it is processed if this box is checked, and positive voltage is in the up direction.  When the box is NOT checked, __prod_name will not adjust the polarity of the incoming AD data and positive voltage is in the down direction.
7. Acquisition Entity    
    Processing Enable 		Enables (checked) or disables (unchecked) the processing of data by the acquisition entity.  If record processing is disabled, records will not be able to be displayed, sent to NetCom or saved to a file.  Raw data file processing will still occur if it is enabled (see -SetRawDataFile -SetRawDataFile).  If acquisition entity processing is toggled during acquisition, CSC record timestamps may no longer be aligned between CSC acquisition entities.  CSC records for all acquisition entities are always realigned when acquisition is started.  This property does not apply to CSG objects.
8.  Data Filename All CSC/CSG records will be saved to the file that is shown right beneath this title.  
9. Input Range Setting Here you will be able to change the value of the input range this CSC/CSG acquisition entity.  This value will be in microvolts.  The input range will always be from the negative of this number to the positive (i.e. in the above image, the input range is from -1000  to 1000 microvolts).  This value cannot be changed while __prod_name is recording.
10. Reference Selection Allows you to select the reference to use for this acquisition entity.  Only references currently allowed by the referencing hardware will be shown in this list.  If a reference you wish to use is not shown in this list, you can select More Reference Options... from the list to launch the HRS Setup.  This dialog will indicate which channels are currently assigned to the local reference buses, 0-7.  From the Acquisition  Entities Properties page, you can unassign one of the references currently in use by a set of acquisition entities.  This action will free up (1) bus line that was assigned the reference.

If an acquisition entity shares one of its AD channels with other acquisition entities, the reference for all acquisition entities using that AD channel will be changed.  In the case of tetrodes and stereotrodes, this will involve more than one AD channel.

Example:   CSC/CSG1's source is AD Channel 0 and TT1's sources are AD Channels 0, 1, 2 and 3.  If the reference for CSC/CSG1 is changed to Subject Ground, not only will AD channel 0 change its reference to Subject Ground, but so will AD Channels 1, 2 and 3.  This happens because all channels on TT1 must use the same reference.
11. Filter Settings See the CSC/CSG Acquisition Entity Filtering Setup for more information.



CSC/CSG Acquisition Entity Filtering Setup

The __lynxsx_hardware_name Acquisition Amplifier utilizes Digital Signal Processing (DSP) filters. DSP filtering uses the computer to filter signals, and does not physically change the signal before it is processed by __prod_name.

1. Low and High Cut DSP Filter Enable __prod_name has the ability to process all signals using digital signal processing (DSP). Checking this box will turn the high cut (low pass)  and low cut (high pass) DSP filter on (checked) or off (unchecked) for the specified acquisition entity.  Changing the enabled state does not affect the actual filter value of the DSP filter, it simply enables or disables the filter.  All channels of an acquisition entity are filtered using the same settings.  Disabling DSP filtering can be used to alleviate CPU load on high channel count systems or older computers.  When the box is unchecked (disabled), you will not be able to change the filter value or number of taps.
2. Low and High Cut  Filter Value Sets the frequency that __prod_name will use for the high cut (low pass) or low cut (high pass) digital signal processing (DSP) filter on all channels of the specified acquisition entity.  The filter frequency has no effect if high cut filtering is disabled.  High cut filters will only allow signals whose frequency is below this value to be recorded by __prod_name and low cut filters will only allow signals whose frequency is above this value.  DSP filters have no effect on data being written to a raw data file (see -SetRawDataFile -SetRawDataFile).  This value is in hertz, and can be any value (including decimal values) between 0.1 Hz and 10000.0 Hz.  This value can only be changed when DSP filtering is enabled.
3. Low and High Cut DSP Filter Taps Digital signal processing (DSP) taps determine the amount of roll-off for the DSP filter.  If you notice the cut filter is allowing signals that are too far beneath (low cut) or above (high cut) your setting to be processed by __prod_name, you may want to increase (low cut) or decrease (high cut) this value.  __prod_name will normally select a tap value that is appropriate for the specific filter frequency.  Lowering the number of taps can be useful to alleviate CPU load on large channel count systems or older computers.  This value can only be changed when DSP filtering is enabled.  If the frequency value is changed to a value that is not available with the current number of taps, __prod_name will change the number of taps to the closest appropriate value.
4. Low and High Cut DSP Filter Type Shows the type of DSP filter being used by __prod_name for the given filter frequency.  This can be one of the following:
  1. FIR :   A finite impulse response filter is being used to filter the data.
  2. DCO:  Uses a running average to remove the DC component from the AC signal.
  3. None:  No DSP filtering is being applied to the incoming data.
5.  DSP Delay Compensation
The delay associated with the current DSP filter settings which __prod_name is automatically compensating for.