gsu (superfx) support [work in progress]

[Eyedunno]

What exactly is the speed difference between this and a normal Super-FX chip (as a percentage) in both 'Normal' and 'Fast' mode?

Is it the whole cart that runs slower, or just special effects using this chip?

I'm not sure there is a simple answer to this. Like I have done some frame-synced comparisons with Star Fox, and the levels are pretty much perfect on normal mode, while the end credits are about 9% too slow. Meanwhile, Yoshi's Island apparently runs a bit too fast on a few occasions just by virtue of having a little less lag.

Fast mode is significantly faster. I haven't actually quantified this, but I would just guess 25-30% faster on Star Fox.

And no, it's obviously not "the whole cart" that runs faster, or it would be a general option, not a GSU option. It's similar to overclocking a Super FX chip, which some modders have done.

[Fitzicks]

I just tested the v10 on my retron3.  starfox, doom, SMB2, dirt trax all seem to be working fine!

[jon_bone]

I tried to copy the files over to the sd card but its says its write protected. How do I remove this write protection?

[TheShadowRunner]

I tried to copy the files over to the sd card but its says its write protected. How do I remove this write protection?

[jon_bone]

It still won't let me copy them.

[iwasaperson]

v9+ (unofficial) was the only version that had new "fpga_base.bit" file, v10 does not. should I restore the original "fpga_base.bit" I had before, or leave it? what does it do? thanks

You should use the same fpga_base.bit that was included in the older v9+. v10+ doesn't include any changes to that file. fpga_base.bit is the FPGA core that the SD2SNES loads on boot and uses with non-special chip games.

[GreenXarrow]

v9+ (unofficial) was the only version that had new "fpga_base.bit" file, v10 does not. should I restore the original "fpga_base.bit" I had before, or leave it? what does it do? thanks

You should use the same fpga_base.bit that was included in the older v9+. v10+ doesn't include any changes to that file. fpga_base.bit is the FPGA core that the SD2SNES loads on boot and uses with non-special chip games.

people who start with v10, will likely have older fpga_base.bit
A42667646176B936D8810980A975344C

unless they caught the previous link in this thread for v9+ (unofficial)
FE1900267952E124285E0337F4391078

what's different between the two? thanks

[Hexatendo]

It still won't let me copy them.

It may be your computer. Try another computer. If it doesn't work, try another sd card.

What exactly is the speed difference between this and a normal Super-FX chip (as a percentage) in both 'Normal' and 'Fast' mode?

Is it the whole cart that runs slower, or just special effects using this chip?

Thanks,

Technically speaking, The GSU-2 (Fast speed) is 200% faster than GSU-1 (Normal Speed). It essentially doubles the processor speed with the GSU-2. I have tested it, and sometimes it clocks in normally with GSU-2, though that normally happens with things like a lot of objects on screen.

[iwasaperson]

people who start with v10, will likely have older fpga_base.bit
A42667646176B936D8810980A975344C

unless they caught the previous link in this thread for v9+ (unofficial)
FE1900267952E124285E0337F4391078

what's different between the two? thanks

The v9+ fpga_base.bit includes ikari_01's 1CHIP brightness fix, and the fpga_base.bit included in Redguy's firmware is identical to the official fpga_base.bit included in the latest SD2SNES firmware. Without replacing the fpga_base.bit file, the 1CHIP brightness option will do nothing (or worse, break something if it changes something that it's not supposed to since bit 6 in the FPGA [the bit that controls the fix] would be undefined).

[Alvis]

The GSU-2 (Fast speed) is 200% faster than GSU-1 (Normal Speed). It essentially doubles the processor speed with the GSU-2.

Wait, those aren't the same thing. "200% faster" would be triple the original speed, not double. Double is 100% faster.

[James-F]

"Normal" will run GSU-1 and GSU-2 games at proper speed as the game intended, it is the game itself that selects between GSU-1 or GSU-2 (10MHz or 20MHz).
"Fast" will run the GSU FPGA core at maximum speed the SD2SNES FPGA will allow, effectively much faster than any real GSU chip.

On "Fast", games that are clock speed (MHz) sensitive, will run much faster than the developer intended, most noticeable is Star Fox, and Stunt Race FX.
Game that are not clock sensitive like Yoshi's Island or Doom will run properly but without the occasional stuttering in graphical heavy scenes.

It is recommended to leave the GSU speed at "Normal" for authentic experience for all GSU games.

[adimifus]

powerslide fix in v10? the demo is a jittery mess. whats fixed? thanks.

I have the same problem. Moving the camera around works fine, but when I switch to the driving mode, the camera freaks out and all I can do is move the dot on the steering wheel. The A/B/X/Y buttons don't do anything. All I can do is take it back into the initial camera mode, where it works fine again.

[ErivandoXP]

powerslide fix in v10? the demo is a jittery mess. whats fixed? thanks.

I have the same problem. Moving the camera around works fine, but when I switch to the driving mode, the camera freaks out and all I can do is move the dot on the steering wheel. The A/B/X/Y buttons don't do anything. All I can do is take it back into the initial camera mode, where it works fine again.

Did you try to hold the "B or Y" button for a few seconds? (The car moves forward)

Here it works.

Edit.:
Hold Y to gas.
Hold B to reverse.

[dvd2vcd]

powerslide fix in v10? the demo is a jittery mess. whats fixed? thanks.

I have the same problem. Moving the camera around works fine, but when I switch to the driving mode, the camera freaks out and all I can do is move the dot on the steering wheel. The A/B/X/Y buttons don't do anything. All I can do is take it back into the initial camera mode, where it works fine again.

Did you try to hold the "B or A" button for a few seconds? (The car moves forward)

Here it works.

can you make a quick video showing us please?

[ErivandoXP]

powerslide fix in v10? the demo is a jittery mess. whats fixed? thanks.

I have the same problem. Moving the camera around works fine, but when I switch to the driving mode, the camera freaks out and all I can do is move the dot on the steering wheel. The A/B/X/Y buttons don't do anything. All I can do is take it back into the initial camera mode, where it works fine again.

Did you try to hold the "B or A" button for a few seconds? (The car moves forward)

Here it works.

can you make a quick video showing us please?

Yes, here:
https://youtu.be/oG5vg5tAsgA

My SNES Fat Rev 2, PPU1 1, PPU2 3.
FW Unofficial-GSU-v10+

Sorry for the bad vídeo.

Edit:
Hold the "button Y" until the car moves forward. (It takes a few seconds for it to move)
If you try to go back, the camera is glitch.