Legible SNES Schematics

Discussion of hardware and software development for Super NES and Super Famicom.

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creaothceann
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Re: Legible SNES Schematics

Post by creaothceann » Mon Dec 11, 2017 7:01 pm

Wikipedia says the Super FX can upload graphics from the cartridge to VRAM. Shouldn't therefore the PA lines on the connector be bidirectional?
My current setup:
Super Famicom ("2/1/3" SNS-CPU-GPM-02) → SCART → OSSC → StarTech USB3HDCAP → AmaRecTV 3.10

lidnariq
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Re: Legible SNES Schematics

Post by lidnariq » Mon Dec 11, 2017 7:04 pm

There is only one bus master in the SNES, and that's the S-CPU and its DMA unit. The SFX is not what's doing the uploading.

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Señor Ventura
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Re: Legible SNES Schematics

Post by Señor Ventura » Wed Dec 13, 2017 2:48 pm

I always believed that DMA can transfer tiles directly from the rom to the vram... and with an sfx we still have the dma doing the same job.

The SFX don't do anything in that way.

tepples
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Re: Legible SNES Schematics

Post by tepples » Wed Dec 13, 2017 5:21 pm

It can.

DMA transfers data from one bus to the other. ROM and cart RAM are on bus A, and the PPU's VRAM data port is on bus B. The console's WRAM is on bus A or bus B (but not both at once). DMA from cart RAM to WRAM pauses the 65816, and I think the GSU is paused as well.

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Firebrandx
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Re: Legible SNES Schematics

Post by Firebrandx » Sun Dec 31, 2017 8:00 pm

OP's link is broken. Anyone have a mirror link?

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sanni
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Re: Legible SNES Schematics

Post by sanni » Mon Jan 01, 2018 11:05 am

Not sure if it's the most recent version
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snes_schematic_color.pdf
(724.91 KiB) Downloaded 231 times

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whicker
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Re: Legible SNES Schematics

Post by whicker » Mon Jan 01, 2018 11:09 pm

I think the commas went away, or something.

https://wiki.superfamicom.org/schematic ... nd-pinouts

lidnariq
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Re: Legible SNES Schematics

Post by lidnariq » Mon Jan 01, 2018 11:56 pm

Here's the last version of snes_schematic_color I have, four minor revisions newer than what sanni posted-
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snes_schematic_color.pdf
version 1.5, internal date stamp of 2014 Feb 24
(269.54 KiB) Downloaded 263 times

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Firebrandx
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Re: Legible SNES Schematics

Post by Firebrandx » Tue Jan 02, 2018 12:29 am

whicker wrote:I think the commas went away, or something.

https://wiki.superfamicom.org/schematic ... nd-pinouts
If you click on that link you posted, you'll see all the schematic file links are broken. :roll:

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