Looking for interchangeable PPU chips (palette specific)

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Looking for interchangeable PPU chips (palette specific)
by on (#233733)
When I sent my NES to be modded with the hi-def kit, I was told the ppu had was having difficulty with the hdmi, so I had REV G chip inserted.

Growing up, the front loader I had, had vibrant colors. Now with PPU swapped, the colors look almost washed, and a slight difference in tint too.

I've loaded different palette files within the hi-def menu, but none are to my liking. I spoke to Kevtris's right hand man, and found out you can swap out the PPU, its not soldered.

My question is, is there a site that sells the different revisioned PPU chips, so I can swap and test?

Thanks!
Re: Looking for interchangeable PPU chips (palette specific)
by on (#233735)
The HiDefNES completely ignores that property of the PPU and replaces it with its own color generation. Desaturation ... or more accurately, over saturation ... of your NES when you were growing up was due to dubious adjustments on the TV.

If you want to recreate, use the "saturation" setting in your TV, not a different PPU.
Re: Looking for interchangeable PPU chips (palette specific)
by on (#233775)
I had 2 frontoaders eons ago, and they both produced different color output on the same tube TV I had.

But my idea is pointless from what you described. Is there a way to modify the contents of the update .NES file for the hidefnes, so I can alter the palette settings for one of the selectable palette choices from the menu?
Re: Looking for interchangeable PPU chips (palette specific)
by on (#233828)
Well, if you're up for scary things that could possibly irreparably break everything, you could try hex editing the fusemap in the firmware update. Quickly checking out "HiDefNES Update V3.01.nes", I strongly suspect that the palettes are stored in YUV, starting at file offset 0x5C010. Each palette lookup appears to be spaced every 2048 bytes. Full 512-color palettes seem to be present. The monochrome palette seems to be most obvious (at file offset 0x5D810) because every 2nd and 3rd bytes are 0x80:
Re: Looking for interchangeable PPU chips (palette specific)
by on (#233900)
Thank you for this. :-)
Re: Looking for interchangeable PPU chips (palette specific)
by on (#233906)
I'm pretty sure the updater does a CRC check, so you might also need to hack the NES program, if you change the data.
Re: Looking for interchangeable PPU chips (palette specific)
by on (#233992)
Thanks for the tip on the crc.