The most recent version of this page is a draft.
This version (10 May 2021 16:16) was approved by Prasad Kamath.The Previously approved version (10 May 2021 15:15) is available.
This version (10 May 2021 16:16) was approved by Prasad Kamath.The Previously approved version (10 May 2021 15:15) is available.This is an old revision of the document!
Table of Contents
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Software debounce
Description
The contacts of mechanical switches and encoders can “bounce” when changing positions; meaning the voltage may fluctuate between states several times during the transition period. When the transition is not clean erroneous states can be set in your system. This block debounces (removes the transition ripple) from a signal, by waiting a specified amount of time between sampling periods. This provides a clean transition signal to the output.
Usage
Typically, this block is used to debounce a GPIO input signal.
To use this block, drag it into the schematic and connect the input to a GPIO signal.
The debounce time control sets the time constant for the debouncer, in samples; the default is 20. For best results adjust the value by trial and error for whatever hardware is connected to the GPIO input.
Targets Supported
| Name | ADSP-214xx | ADSP-215xx/ADSP-SC5xx | ADAU145x/1456x |
|---|---|---|---|
| —————————————- | —————————————— | ————————————————-- | ——————————————- |
| Software debounce | Not supported | Not supported | Sample |
Pins
Input
| Name | Type | Description |
|---|---|---|
| ———————— | —————————— | ———————————————————— |
| Input0 | Audio | Audio input to the software debounce |
Output
| Name | Type | Description |
|---|---|---|
| ———————- | ————————— | —————————————————————————-- |
| Output0 | Audio | Audio output from the software debounce |
Configurable Parameters
| GUI Parameter Name | Default Value | Range | Function Description |
|---|---|---|---|
| —————————————- | ———————- | ————————————- | —————————————- |
| CountMax | 20 | [0, 1000] | Sample counter for the Debounce time on the Rotary Encoder |
DSP Parameters
| Parameter Name | Description | ADAU145x/ADAU146x |
|---|---|---|
| —————————- | ——————————————————————————————————- | ——————————— |
| countmax | Time constant for the debouncer | Fixed Point 32.0 |
DSP Parameter Computation
Not applicable
resources/tools-software/sigmastudiov2/modules/gpioconditioning/softwaredebounce.1620656184.txt.gz · Last modified: 10 May 2021 16:16 by Prasad Kamath