NES version of Balloon Fight resets on a VS red tent, why?

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lidnariq
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Re: NES version of Balloon Fight resets on a VS red tent, wh

Post by lidnariq » Sun Sep 18, 2016 12:46 am

You know, you're almost certainly right. There are probably just the two addresses, and everything else almost certainly does nothing at all.

Extra complexity wouldn't really serve any purpose but to increase costs, especially since the game never tests anything else.

That said ... here's a new version with the two new tests I described. Locations of not-zeroes are what's interesting.
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ARBIBB_tests_2016_09_17.7z
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lupin3rd
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Re: NES version of Balloon Fight resets on a VS red tent, wh

Post by lupin3rd » Sun Sep 18, 2016 8:49 am

lidnariq wrote:Locations of not-zeroes are what's interesting.
Question about that... I noticed that whatever the MSB of the address was, is what the entire page would return (in flipped order).

e.g. If I flipped to address 0x5401, the entire page would be full of "45". If I flipped to 0x5101, the page would be full of "15". Should I go ahead and burn the test and run it, or did you want to make modifications based on what I just mentioned?

If you already noticed that, my apologies for restating the obvious. :)
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lupin3rd
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Re: NES version of Balloon Fight resets on a VS red tent, wh

Post by lupin3rd » Sun Sep 18, 2016 9:14 am

Scratch that -- went ahead and burned and verified results. :-)
"Can I keep his head for a souvenir?" -Max

lidnariq
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Re: NES version of Balloon Fight resets on a VS red tent, wh

Post by lidnariq » Sun Sep 18, 2016 11:25 am

All right. It's fully decoded, with the exception of A11, so the two registers are simply only at $5E00 and $5E01 and a mirror at $5600 and $5601. There's nothing else there.

I've written a silly implementation of the yielded LFSR but it doesn't match. Maybe the 127 is somehow folding multiple bits of state into each bit of output.

Certainly the bit right at the beginning where the bits disappear as:

Code: Select all

FF 1111 1111
FD 1111 1101
F5 1111 0101
F4 1111 0100
B4 1011 0100
shows that the bits are at the very least shuffled.

I think no further programs need to be run on the Vs. System. At least, nothing comes to mind. Thank you very much for your help!

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lupin3rd
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Re: NES version of Balloon Fight resets on a VS red tent, wh

Post by lupin3rd » Sun Sep 18, 2016 11:52 am

lidnariq wrote:I think no further programs need to be run on the Vs. System. At least, nothing comes to mind. Thank you very much for your help!
Glad I could help! I'm kinda sad now that we're done! ;) Well, I guess I can turn my attention full-time to solving my NES-on-VS mirroring issues. May also try some homebrew on the NES and VS now, I read through the NESDoug tutorials that were linked from one of the forum posts, and it actually looks like the NES is really easy to develop low-level games on, so I'm excited about the prospect now.

Thanks again, everyone!

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Zepper
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Re: NES version of Balloon Fight resets on a VS red tent, wh

Post by Zepper » Tue Feb 21, 2017 2:49 pm

bump :mrgreen:

What's the problem with the .NES test file header? My emu detects "dirty header", and disabling it, I got mapper 206.

lidnariq
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Re: NES version of Balloon Fight resets on a VS red tent, wh

Post by lidnariq » Tue Feb 21, 2017 3:09 pm

All of my tests have valid NES2.0 headers.

Vs Atari R.B.I. Baseball is mapper 206.

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