Emulator's first run - big time fail

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Petruza
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Emulator's first run - big time fail

Post by Petruza » Sat Jun 12, 2010 5:28 pm

Ok, I finished the bare minimum CPU and PPU implementation to run my emulator and see some results.
I ran Donkey Kong, Balloon fight and Super Mario Bros, besides that all that I got is the tile 0 all over the screen, it ran at no more than 3 fps.
Ok, it's on debug mode, it should run faster on release, but still!
In your experience were your emulators such a failure on the first run?

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blargg
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Post by blargg » Sat Jun 12, 2010 6:58 pm

I didn't try stepping over a continent on the first run of my emulator :)

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James
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Re: Emulator's first run - big time fail

Post by James » Sat Jun 12, 2010 8:43 pm

Petruza wrote:In your experience were your emulators such a failure on the first run?
yes :lol:

Sounds like you're making good progress, though. You'll get there, and these challenges will make it all the more rewarding when you do.

By the way, when I was at this stage of development, I found Chris Covell's Zelda Title Screen simulator to be a good test ROM as it simply displays a static background.

Good luck!

NickMass
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Post by NickMass » Sat Jun 12, 2010 10:44 pm

When I finished the PPU on my emulator initially it was pretty useless and I happened to of kept a screen shot of how it looked running Balloon Fight for the first time

Image

Palettes and the background were completely broken but surprisingly the sprites worked kinda okay. Despite all the issues I was still pretty pumped to see it outputting anything graphically for the first time and it eventually got better. :D

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Petruza
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Post by Petruza » Sun Jun 13, 2010 7:07 am

Thanks james for the ROM suggestion. I'll try it.
I'm thinking of making a full-fledged visual debugger with ROM, RAM and VRAM watches, instruction stepping and breakpoints, to see really what's happening.

NickMass, that's a great idea, I'll keep screenshots of the early development to see the progress.
By watching your screenshot I think you did the same as I did, made a static pallete of red, green and blue to see some output before caring about palettes, right?

Edit: Actually James, Thank you very much!!! with that demo ROM at least I know the rendering works (kind of) yeah!

Image

NickMass
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Post by NickMass » Sun Jun 13, 2010 11:31 am

Petruza wrote: By watching your screenshot I think you did the same as I did, made a static pallete of red, green and blue to see some output before caring about palettes, right?
Yeah, that is exactly what I did, though there probably could of been some better colors to pick because it wasn't exactly easy to see what was going on.

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Petruza
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Post by Petruza » Sun Jun 13, 2010 11:34 am

Actually looking at my own screenshot, it seems to be what I DIDN'T do, lol.
Strange, the previous test was just loading the tiles and displaying them all together, and they were all RGB, I wonder why this strange palette came out of the Zelda demo.

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