[sdiy] Soft ADSR ways?

[Scott Gravenhorst]

Matthew Smith <matt at smiffytech.com> wrote:
>Quoth karl dalen at 13/02/11 20:36...
>> How many ways could one do an ADSR in? Which one are
>> fastest and which one are fast and code efficient??
>...
>> KD (dont talk math with me im crap at it)
>
>I am designing an AD(H)SR generator and I also have math problems :-)
>
>So far, I have identified that I need to find out how to do integer 
>division, in simple steps.
>
>But because I am going to have switchable linear/exponential A and D, I 
>will be using table lookup for this - it will then be a case of dividing 
>the time (0-255, I'm doing 8-bit) to get the delay between pushing table 
>entries to the DAC.
>
>I reckon that as ADSR waveforms are so slow, in microcontroller terms, 
>calculation time should not be a big worry.
>
>-- 

As a side note - I would also consider switchable linear/exponential [R] release.

-- ScottG
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-- Scott Gravenhorst
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