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Up Down Control LUT


This block takes in two inputs, one up and one down, and uses them to generate an index for a lookup table. The starting index is pre-loaded into an interface register and the up/down inputs increment or decrement the value.


  1. Drag the block into your schematic.
  2. Connect the red control inputs to GPIOs that have been conditioned by Push and Hold, or to the outputs of the Rotary Encoder.
  3. Connect the yellow input pin to an Interface Read block.
  4. Connect the yellow output to an Interface Write block, with the same register selected for both the interface read and write blocks.
  5. The output will be the value in the table corresponding to the index.

Targets Supported

Up Down Control LUT Not supported Not supported Sample



Input0Controlincrement input (up)
Input1Controldecrement input (down)
Input2LogicConnected to a software interface register - reads the last stored value at startup


Output0Control Output signal
Output1LogicConnected to a software interface register - writes the last output value

Configurable Parameters

GUI Parameter NameDefault ValueRangeFunction Description
—————————————- ———————- ———————- ———————————————————————————————————
ByPassEnable disable enable/disable bypasses the LUT value looked up
NoOfTableValues33 pts[2, 800]Sets the table size: the  number of points used in the volume table curve.
TableValues1[-16, 15.99]The table points are the actual gain values for the volume curve in linear representation. Although the range supports the full values of [-16, 15.99] the table values should generally be between [0, 1] for proper gain adjustments. The user has full control in this table to add a linear, logarithmic of custom gain volume curve

DSP Parameters

Parameter NameDescriptionADAU145x/ADAU146x
————————--———————————————————————————————————————————- ———————————
maxindexmaxnumber of table pointsFixed Point 32.0
table_p0All the points in the table are written to the DSP in their linear gain formatFixed Point 8.24

DSP Parameter Computation

Not applicable

/srv/ · Last modified: 12 May 2021 14:28 by Prasad Kamath