Format of inputs and outputs
Thread Summary
The user asked if a Delta-Sigma encoder/decoder (CS42488) output can be used directly in a DSP and how to implement a log volume control. The final answer confirms that the lookup tables are flexible and can handle different value ranges. The engineer provided a sample program for controlling gain via an index-controlled table to avoid zipper noise and sudden gain shifts.AI Generated Content
Hi,
On the board we use a Delta-Sigma encoder/decoder (CS42488).
Can we use directly this format in the DSP? or do we have to do some Delta-Sigma to uniform conversion before ?
Thanks for your help, I can now implement a Log Volume control using a lookup table (-6db to +6dB).
I found the problem: inputs are in range [0..x] but look up tables are in range [1..x] (very strange)
Best regards,
Patrice
Audio Signal Processors
software
SigmaDSP Audio Processors
adau1462
Hello Patrice,
The tables are really flexible such that you can have integer or fixed point values to control the tables and then the same for the outputs. They are independently selected with the tiny hidden buttons.
Now your program is very close. I wrote a program a few years ago that does this. I did it a little differently in that I used a parameter update block to update the target gain of a volume control that is slewed so you will not get zipper noise or sudden shifts in gain.
Here is the program
2117.ADAU1452 AUXADC Controlled Gain via an index controlled table for custom values.dspproj
Dave T
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