Noise pitch is different in emulator vs hardware?

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kliepatsch
Posts: 258
Joined: Thu Oct 08, 2020 9:54 pm

Re: Noise pitch is different in emulator vs hardware?

Post by kliepatsch »

Thank you! Much appreciated.

If for some reason, the down-clocking of the LFSR is too difficult to implement, here's another way of decorrelating subsequent iterations:

We could cut the sequence of 65535 values short somehow, which makes the total number of samples less similar to a multiple of 512.
E.g. we could reset the LFSR content to $FFFF when the current value is equal to the one that comes N iterations before $FFFF would occur naturally, with N something of the order of 10 or 20 maybe.

Or the other way around: when the LFSR content reaches $FFFF, we set its content to the value that would occur naturally 10 or 20 iterations after $FFFF.
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kliepatsch
Posts: 258
Joined: Thu Oct 08, 2020 9:54 pm

Re: Noise pitch is different in emulator vs hardware?

Post by kliepatsch »

Let's hope it is as easy as you suggest.
DragWx
Posts: 400
Joined: Tue Mar 07, 2023 9:07 pm

Re: Noise pitch is different in emulator vs hardware?

Post by DragWx »

I wouldn't expect there to be any problems with changing how the LFSR is clocked, because, in terms of circuitry, it'd just be changing what signal drives the CLK input of the shifter, and I think the signal exists already because it's used to sequence channel updates.

Nevertheless, if this change were implemented, I'd greatly appreciate it and it would be the thing that makes me (finally) update my hardware away from r47. :P
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