This version (12 May 2021 12:50) was approved by Prasad Kamath.The Previously approved version (12 May 2021 12:44) is available.Diff

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Sweep Look Up Sine


The Sweep (Lookup/Sine) block generates a sinewave that sweeps from a start to an end frequency. The sweep speed is determined by the number of steps and cycles per step.


Enter the desired start and stop frequency and step size using the edit controls:

  • Initial Freq
    • The frequency at which to begin the sweep.
  • Ending Freq
    • The frequency at which to end the sweep.
  • Step
    • Determines the number of steps in the sweep.
  • Reset
    • Resets the current sweep frequency to the “Initial Freq”.
  • Sweep
    • Starts the frequency sweep.
  • Speed
    • Sets the sweep speed, the relative duration of each sweep step.

A valid slope range will be computed depending on the step size entered. The ending tone will be held until reset is clicked, which returns to the initial frequency. The plot below shows the correlation for sweep plots with varying step sizes and slopes.

Targets Supported

Name ADSP-214xx ADSP-215xx/SC5xx ADAU145x/146x
———————————-- ———————— ——————————-- —————————-
Sine Look up Sweep Not SupportedNot Supported Sample



——————————— ———————————- ————————————--
OutputAudioOutput channel

Configurable Parameters

GUI Parameter NameDefault ValueRangeFunction Description
—————————————- ———————- —————————— —————————————-
InitialFrequency1500 to 0.5* sample rateSets the initial frequency for sinetone sweep
EndFrequency100000 to 0.5* sample rateSets the final/end frequency for sinetone sweep
SlewStep161 to 23 Slew step
Slope1 0 to 12 Gain, the sinetone wave to be multiplied in the lookup
Sweep1 0(off)/1(on) Switch on and off the sine sweep

DSP Parameters

Parameter NameDescriptionADAU145x/146x
—————————-- ——————————————————————— ————————————————
increment1increment value for initial frequencyFixPoint8d24
increment2increment value for endfrequencyFixPoint8d24
slopeGain, the sinetone wave to be multipliedFixPoint8d24
step slew stepFixPoint8d24
ison Enabled/Disabled the sweepFixPoint8d24

DSP Parameter Computation

increment1= InitialFrequency/(FS/2)
increment2= EndFrequency/(FS/2)
slope= Slope* 2^(SlewStep-23)
step = 2 ^ (-1* SlewStep)
ison = Sweep
FS, Where fs is frequency and FS is the sampling rate

resources/tools-software/sigmastudiov2/modules/sources/sweeplookupsine.txt · Last modified: 12 May 2021 12:50 by Prasad Kamath