SampleAndHold

Overview

Sample and hold module

Discussion

An audio rate sample and hold module for use with the Audio Weaver environment. The module has two input pins: trigger and data. The trigger signal block size must be either 1 or the same block size as the input signal. If the trigger signal block size is 1 then the trigger applies to all the samples.

The output samples follow the input samples whenever the trigger sample is not zero. The first zero sample in the trigger holds the prior input sample for output until the next non-zero trigger sample. The module is designed to work with multichannel data.

There are two operating modes. If the trigger pin has a single channel, then the trigger is applied to all of the interleaved data channels. Otherwise, if the trigger has the same number of channels as the data, then a separate trigger is applied to each channel.

Internally, the module stores the sampled data within the value array. This array has 1 sample per input channel.

Module Pack

Advanced

ClassID

classID = 1316

Type Definition

typedef struct _ModuleSampleAndHold
{
ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
FLOAT32* value;                               // Holds the last data value which was sampled. This is an array so that multiple channels can be supported.
} ModuleSampleAndHoldClass;

Variables

Properties

Name	Type	Usage	isHidden	Default Value	Range	Units
value	float*	state	0	[1 x 1]	Unrestricted

Pins

Input Pins


Name	trig
Description	trigger signal
Data type	int
Channel range	Unrestricted
Block size range	Unrestricted
Sample rate range	Unrestricted
Complex support	Real


Name	in
Description	input data
Data type	{float, int, fract32}
Channel range	Unrestricted
Block size range	Unrestricted
Sample rate range	Unrestricted
Complex support	Real

Output Pins


Name	out
Description	output data
Data Type	{float, int, fract32}

Matlab Usage

File Name: sample_and_hold_module.m 
 M=sample_and_hold_module(NAME) 
 Creates a sample and hold module for use with the Audio Weaver 
 environment. 

 Arugments: 
    NAME - name of the module.