Can someone run an MMC2/MMC4 test ROM for us?

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tepples
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Can someone run an MMC2/MMC4 test ROM for us?

Post by tepples » Fri Jun 27, 2014 5:51 am

FHorse is trying to use my test ROM to get MMC2 and MMC4 support working in puNES. But I want to make sure that the test ROM itself is correct. I don't want it to be relying on differences between the emulators and PowerPak on which I tested it and the actual hardware. So I'll need someone to rip up one of these NES or Famicom games, solder in EPROM sockets.
  • Mike Tyson's Punch-Out!!
  • Punch-Out!!
  • Famicom Wars
  • Fire Emblem
  • Fire Emblem Gaiden
Then try Holy Diver Batman on it and tell us what four-digit code it produces.

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Bregalad
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Re: Can someone run an MMC2/MMC4 test ROM for us?

Post by Bregalad » Fri Jun 27, 2014 6:20 am

Can't you make a test ROM that can work by hotswapping ? This would allow me to use MMC2 without butchering my Punch-Out card. As for MMC4 unfortunately I can definitely not help.

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Re: Can someone run an MMC2/MMC4 test ROM for us?

Post by tepples » Fri Jun 27, 2014 6:29 am

The MMC2/MMC4 test kernel in Holy Diver Batman runs in RAM, meaning it could be turned into a hot-swap test ROM. But I'm not quite ready to spend money on doing so myself. To test a hot-swap ROM, I'd have to mod my own front-loading NES to disable the CIC and then buy a copy of MTPO.

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infiniteneslives
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Re: Can someone run an MMC2/MMC4 test ROM for us?

Post by infiniteneslives » Fri Jun 27, 2014 12:44 pm

I'll give it another try on my boards this weekend. I can't get myself to rip up my original carts. It would be subject to potential inconsistencies between my design and the original ASICs, but I have tested all those games with no issues FWIW.
If you're gonna play the Game Boy, you gotta learn to play it right. -Kenny Rogers

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Re: Can someone run an MMC2/MMC4 test ROM for us?

Post by tepples » Fri Jun 27, 2014 3:14 pm

infiniteneslives wrote:It would be subject to potential inconsistencies between my design and the original ASICs
The problem is that such inconsistency is kind of what I was trying to discover. I don't want puNES to end up changing from the correct behavior to your misbehavior that happens to run the commercial games.

I wish emulators supported hot swap.

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rainwarrior
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Re: Can someone run an MMC2/MMC4 test ROM for us?

Post by rainwarrior » Fri Jun 27, 2014 3:49 pm

tepples wrote:I wish emulators supported hot swap.
It's not convenient, but you can do the equivalent with prepared savestates.

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Re: Can someone run an MMC2/MMC4 test ROM for us?

Post by lidnariq » Fri Jun 27, 2014 4:20 pm

I'm not clear on why you feel the MMC2 is a sufficiently more complex thing than the MMC1 that it needs a strict hardware verification while the MMC1 didn't? (Or did I miss something?)

We have the patent documentation for the MMC2, as well as Farid's found discrete logic clone, and BootGod verified that his copy of PunchOut!! acts in the same way as the discrete logic implementation would.
Namely:
lidnariq in a PM to BootGod wrote: make sure that reading from $xFD8 or $xFE8 changes both the PPU's $0000 bank and $1000 bank, and then find out whether reading from $xFD9 or $xFE9 only changes the PPU's $1000 bank.
BootGod in a PM to lidnariq wrote:It works exactly as you expected :)
For timing reasons, the bank switch can happen no earlier than the rise of PPU /RD and no later than five pixels later (ALE /RD ALE /RD ALE), and there's no way for the CPU to see where in that range the bankswitch happens.

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Re: Can someone run an MMC2/MMC4 test ROM for us?

Post by tepples » Fri Jun 27, 2014 4:53 pm

lidnariq wrote:I'm not clear on why you feel the MMC2 is a sufficiently more complex thing than the MMC1 that it needs a strict hardware verification while the MMC1 didn't? (Or did I miss something?)
What you missed were IRC sessions months ago where I got hardware verifications of MMC1 and MMC3 from someone else.
We have [...] Farid's found discrete logic clone
Then can we run it on Farid's circuit? I just want to avoid this being like NEStress, where a test passes on inaccurate emulators but fails on hardware.

On the other hand, it might be better to delay running the test until I've had a chance to look over it manually to add specific result codes that distinguish MMC2-style behavior from MMC4-style behavior.

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Re: Can someone run an MMC2/MMC4 test ROM for us?

Post by Memblers » Mon Jun 30, 2014 7:31 pm

Tepples, I have the Playchoice version of Punch Out, in which the PRG is EPROM and CHR is maskROM (it's the only Playchoice game that isn't identical to it's NES release, it uses WRAM as well). If you don't mind remapping the character set and bank select to suit it, I could test it. I have a batch of EPROMs I'll be erasing next week, I could do it then.

If you want to go that route, there was a pretty cool custom charset macro posted in this thread:
viewtopic.php?f=2&t=11112&start=15

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Re: Can someone run an MMC2/MMC4 test ROM for us?

Post by tepples » Mon Jun 30, 2014 7:58 pm

Thanks. We'll have to get in touch through PM to discuss this.

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