## Wave Planner and WavePlayer

Topics:

- Overview
- Waves
- Binary Wave Files
- Text Wave Syntax
- Remote Script Software Start
- Remote Script Triggered Start

### Overview

SpikeGLX contains easy to use tools for stimulus waveform output.

- Use the SpikeGLX ‘Wave Planner’ dialog under the ‘Windows’ menu, to create ‘wave’ files that you can then load, trigger and control using our remote scripting API.

- Wave files can be executed using either OneBox, or NI devices with waveform capable analog output features.

### Waves

A ‘wave’ is a pair of descriptor files:

1. A mywave.meta file is in human readable ‘ini’ format, just like a SpikeGLX run.meta file. It’s a handful of plain text ‘keyword=value’ pairs. Here’s an example:

    [WaveMeta]
    sample_frequency_Hz_dbl=10000
    wave_Vpp_dbl=2
    device_Vpp_dbl=5.0
    data_type_txt_i16_f32=txt
    num_samples_i32=0

2. The corresponding data file can have three formats, selected by the data_type_txt_i16_f32 meta item:

1. ‘txt’ data type: file mywave.txt contains a plain text script that generates the samples.
2. ‘i16’ data type: file mywave.bin contains the numerical samples as 16-bit signed integers.
3. ‘f32’ data type: file mywave.bin contains the numerical samples as floats.

IMPORTANT:

- All wave descriptors should live in the `_Waves` subfolder within the SpikeGLX application folder.

- API functions that take a wave name should be given just the wave base-name itself, stripped of any path or file extension. For example, if your metafile full path was ’C:/SpikeGLX_stuff/SpikeGLX/_Waves/mysinwave.meta’, then you should refer to this simply as ‘mysinwave’.

NOTE: Target device:

The metadata and binary data that describe a wave are device independent. However, the dialog contains a field called `Target device`. At present, the choices are {NI, OneBox}. The purpose is to constrain the `Device V` selections for maximum voltage. That is NI is flexible allowing +/- {2, 5, 10}V output, while OneBox is limited to +/- 5V. The `Target device` merely controls the “sanity checking” of the voltage ranges.

### Binary Wave Files

The binary formats are provided to allow maximum flexibility to generate samples using your own external tools. Valid binary data follow these rules:

- num_samples_i32 should be set to the accurate count of samples in the *.bin file.
- num_samples_i32 should be an even number.
- num_samples_i32 should not exceed 16777214.
- i16 data should be in the range [-32768,32767]. Upon loading, your values will be multiplied by (wave_Vpp_dbl / device_Vpp_dbl).
- f32 data should be in the range [-1.0,1.0]. Upon loading, your values will be multiplied by (32767 * wave_Vpp_dbl / device_Vpp_dbl).

> The scaled values are forced to range [-32768,32767].

> Although you must generate the .bin file and its samples yourself, you can use the SpikeGLX Wave Planner dialog to edit the frequency and voltage scales in the .meta file.

### Text Wave Syntax

Use the Wave Planner ‘Data’ text box to write your generator script.

Our wave mini-language uses four commands that can be strung together in any combination:

- level( V, t_ms ) : Generate samples of amplitude V (float) in range [-1.0,1.0] for time span t_ms (float) milliseconds.

- ramp( V1, V2, t_ms ) : Generate samples with linearly ramping amplitude from V1 to V2 (floats) each in range [-1.0,1.0] for time span t_ms (float) milliseconds.

- sin( A, B, f_Hz, t_ms ) : Generate a sine wave with amplitude A (float), baseline B (float), where (A + B) is in range [-1.0,1.0]. The sine wave has frequency f_Hz (float) and total time span t_ms (float) milliseconds.

- do N { } : Repeat whatever is included in curly braces N (integer) times. Nesting of do-loops is permitted.

> White-space (returns, spaces, tabs) are completely ignored. Use space freely to make a script readable.

> At load-time your script is compiled into scaled samples; scale factor: (32767 * wave_Vpp_dbl / device_Vpp_dbl).

Example

    do 5 {
        level(     0,   50 )
        ramp( 0,   0.5, 10 )
        level(     0.5, 100 )
        ramp( 0.5, 0,   10 )
    }

### Remote Script Software Start

MATLAB script ‘wp_soft_start’:

- Plays wave ‘jwave’ at OneBox channel AO-0.
- Playback is triggered by software command.

    function wp_soft_start

        % Handle to SpikeGLX
        hSGL = SpikeGL( '127.0.0.1' );

        % For demo purposes we assume the OneBox is not recording...
        % So we refer to it using its slot index
        ip = -1;
        slot = 21;

        % Load the wave plan
        wave_name = 'jwave';
        OBX_Wave_Load( hSGL, ip, slot, wave_name );

        % Select software triggering and infinite looping
        trigger = -2;
        looping = 1;
        OBX_Wave_Arm( hSGL, ip, slot, trigger, looping );

        % Start playback now, output is always at AO-0
        start = 1;
        OBX_Wave_StartStop( hSGL, ip, slot, start );

        % This section demonstrates a method to capture your
        % wave plan in action. The best pause parameters will
        % depend upon the duration of your wave plan and how
        % fast your SpikeGLX graphs are sweeping
        %
        % Let this play for 1 second
        % Then pause the SpikeGLX Graphs Window for 2 seconds
        % Then resume Graphs for 5 seconds
        pause( 1.0 );
        PauseGraphs( hSGL, 1 );
        pause( 2.0 );
        PauseGraphs( hSGL, 0 );
        pause( 5.0 );

        % Stop playback
        start = 0;
        OBX_Wave_StartStop( hSGL, ip, slot, start );

    end % wp_soft_start

### Remote Script Triggered Start

MATLAB script ‘wp_trig_start’:

- Plays wave ‘jwave’ at OneBox channel AO-0.
- Playback is triggered when OneBox channel AI-1 goes high.
- User needs to list AI-1 in the XA box of OBX Setup tab.
- We will configure NI device to send TTL rising edge from line-4.
- User needs to wire NI line-4 to OneBox AI-1.

    function wp_trig_start

        % Handle to SpikeGLX
        hSGL = SpikeGL( '127.0.0.1' );

        % OneBox assumed to be recording stream ip=0...
        % So the slot number is ignored in this case
        ip = 0;
        slot = -1;

        % Load the wave plan
        wave_name = 'jwave';
        OBX_Wave_Load( hSGL, ip, slot, wave_name );

        % Select AI-1 triggering and no looping
        trigger = 1;
        looping = 0;
        OBX_Wave_Arm( hSGL, ip, slot, trigger, looping );

        % Configure NI line-4
        digOutTerm = '/PXI1Slot6_2/line4';
        digBits = 0x10; % binary 1 at bit-4, zero elsewhere
        NI_DO_Set( hSGL, digOutTerm, 0 );

        % Start playback now, output is always at AO-0
        NI_DO_Set( hSGL, digOutTerm, digBits );

        % Reset trigger after 50 ms
        pause( 0.05 );
        NI_DO_Set( hSGL, digOutTerm, 0 );

        % This section demonstrates a method to capture your
        % wave plan in action. The best pause parameters will
        % depend upon the duration of your wave plan and how
        % fast your SpikeGLX graphs are sweeping
        %
        % Let this play for 1 second
        % Then pause the SpikeGLX Graphs Window for 2 seconds
        % Then resume Graphs
        pause( 1.0 );
        PauseGraphs( hSGL, 1 );
        pause( 2.0 );
        PauseGraphs( hSGL, 0 );

        % Stop playback
        start = 0;
        OBX_Wave_StartStop( hSGL, ip, slot, start );

    end % wp_trig_start

fin