How to generate a solar-storm waveform with SPC700?

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Raltair
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How to generate a solar-storm waveform with SPC700?

Post by Raltair » Wed Feb 03, 2021 9:29 am

Hi,
i'm new to SPC700 development, I found this very useful datasheet with some info on how to decode BRR samples for the SNES: http://problemkaputt.de/fullsnes.htm#sn ... brrsamples

If you scroll down a bit you'll find waveform examples. I managed to reproduce them but I'm stuck on this one

Code: Select all

   ___     __
  |   |___|  |    _       \ ! /  .  \ ! /  Nibbles=77DE9HZK, Shift=3M, Filter=V
  |_     ____|  _|  --->  - + -  +  - + -  SOLAR STORM wave-form
  __|   |______|___       / ! \  '  / ! \
In my code I use an uint8_t to store the Shift value, but here it seems to use 3M so I expanded it to uint32_t to fit that big number. Filter 'V' seems to be OK with a char, but i'm also confused about Nibbles. 77DE9HZK doesn't work or uses some kind of base bigger than Hexadecimal that I don't know about yet, it seems to be a lot of nibbles anyway.

I'm trying since several days but i can't get the waveform to go backwards like on that drawing. Solar Storm waveform looks so cool i'm sure it also sounds cool, please help !

lidnariq
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Re: How to generate a solar-storm waveform with SPC700?

Post by lidnariq » Wed Feb 03, 2021 12:49 pm

it's a joke...

nocash
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Re: How to generate a solar-storm waveform with SPC700?

Post by nocash » Wed Feb 03, 2021 1:06 pm

As far as I remember, it was mentioned in the japanese programming reference, or in one of the SFC patents.
I am fairly sure that all nibbles are hexadecimal (albeit exceeding the currently known range).
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Raltair
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Re: How to generate a solar-storm waveform with SPC700?

Post by Raltair » Wed Feb 03, 2021 1:57 pm

nocash wrote:
Wed Feb 03, 2021 1:06 pm
As far as I remember, it was mentioned in the japanese programming reference, or in one of the SFC patents.
I am fairly sure that all nibbles are hexadecimal (albeit exceeding the currently known range).
Ah! I knew that there was some black magic built into the SPC700! I may try to go past 0xFF but I don't want to brick the chip... So my next quest is to find these patents... :twisted:

I just hope failing to do a solar storm doesn't ends up with a black hole

nocash
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Re: How to generate a solar-storm waveform with SPC700?

Post by nocash » Wed Feb 03, 2021 4:11 pm

There is also a tech paper from M. China and L. Bennett first published 1993 as a supplement in some copies of Ablaze! fanzine issue 10:
Abstract: Check astrophobolical wheather forecasthoroscope in magazine, then bring APU into low orbit less than 1 light second? ☆ Large heat shield requireddepends on granite estimated to melt at speed rate of one kilometre per minutepossible problem? ☆ Radio transmission won't work in environment, make sure live audience + speaker membranes!!! can survive to enjoy full solar waveform.todo: research ice-cream, better heat shield? LesBee♡♡♡MelChi rockz!
I haven't found the whole article, it was apparently printed (or handwritten?) on cigarette paper.
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nocash
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Re: How to generate a solar-storm waveform with SPC700?

Post by nocash » Sun Feb 21, 2021 2:17 pm

Next cooler thing: Jasmine Harrison has just become the first person ever to cross the Atlantic in a rowing boat with chocolate as main food source.
Edit: Or not the very first person, Katie Spotz seems to have done it earlier, but it's cool anywas.
homepage - patreon - you can think of a bit as a bottle that is either half full or half empty

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