This version (21 Jun 2012 23:07) was approved by William Jahn.The Previously approved version (21 Jun 2012 22:57) is available.Diff

OneShot Fall

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The One Shot Fall block outputs a trigger signal based upon the falling edge of the input signal. At the first falling edge of the input signal, the output signal will go high and remain high. The falling edge of the input signal is defined as any input signal level value changing to a lower signal level value.

Input Pins

NameFormat [int/dec] - [control/audio]Function Description
Pin 0: Inputany - anyInput signal that is monitored for the first falling edge

Output Pins

NameFormat [int/dec] - [control/audio]Function Description
Pin 0: Triggerany - controlOutput flag signal set to “1” in the selected bit position

GUI Controls

GUI Control NameDefault ValueRangeFunction Description
Output Bit Designation28[28.0 Bit26]Sets bit position of the output “1” flag. 28.0 is the default values which represents 1LSB.

DSP Parameter Information

GUI Control NameCompiler NameFunction Description
Output Bit DesignationOneShotFallAlg1output1Actual value written to DSP from the representation of the drop-down menu to select the bit position of the output “1” flag.  

Algorithm Description

The following graph shows the output response of the OneShot Fall algorithm, based on a given toggling input signal. There are two different case scenarios:
Case1: The input signal starts high
Case2: The input signal starts low

In the graphs the input signal is only toggling between “1” and “0” however this algorithm will respond to any changes in level of the input signal, thus the first falling edge of a lower input signal will trigger the output to go high.

The format of the “1” output value of the is designated by the drop-down menu. The following table shows the “1” Output that corresponds to the drop-down menu selection.


The following image shows the OneShot Fall block being used. A switch source is connected to the input and then the output of the block is driving a GPIO output. When the switch is clicked “low” the signal sent to the GPIO output will be “high.”

Algorithm Details

Toolbox PathBasic DSP - Logic - Toggle - OneShot Fall
Cores SupportedAD1940
“Grow Algorithm” Supportedno
“Add Algorithm” Supportedno
Subroutine/Loop Basedno
Program RAM5
Data RAM4
Parameter RAM1
resources/tools-software/sigmastudio/toolbox/basicdsp/oneshotfall.txt · Last modified: 21 Jun 2012 23:07 by William Jahn