iNES Mapper 12 (MMC3A?)

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lidnariq
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Re: iNES Mapper 12 (MMC3A?)

Post by lidnariq » Sat May 16, 2020 10:47 am

How is your screenshot so clear? What console are you using?

Ice Man
Posts: 526
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Re: iNES Mapper 12 (MMC3A?)

Post by Ice Man » Sat May 16, 2020 10:47 am

The hack uses MMC5 already.
I guess mapper 12 wasn't good enough of a choice at all.
Your ROM is outdated + not allowed to post ROMs at all.

The screenshot looks like it was taken from an emulator.

Aside from that, you may want to post pictures of your cart/work and double check if all connections are correct.

Ruslansh
Posts: 42
Joined: Sun Apr 28, 2013 3:27 am

Re: iNES Mapper 12 (MMC3A?)

Post by Ruslansh » Sat May 16, 2020 10:56 am

this is an emulator, I changed the title to 4 mapper. On the emulator and on the console, the game works the same.

https://prnt.sc/si0x0j

Ruslansh
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Joined: Sun Apr 28, 2013 3:27 am

Re: iNES Mapper 12 (MMC3A?)

Post by Ruslansh » Sat May 16, 2020 10:59 am

I have rechecked all the connections many times, there are no errors. MMС5 is better, I agree. But I can only collect 12 mappers, I have spare parts for it.

Ruslansh
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Re: iNES Mapper 12 (MMC3A?)

Post by Ruslansh » Sat May 16, 2020 11:07 am


Ruslansh
Posts: 42
Joined: Sun Apr 28, 2013 3:27 am

Re: iNES Mapper 12 (MMC3A?)

Post by Ruslansh » Sat May 16, 2020 11:08 am

Ice Man wrote:
Sat May 16, 2020 10:47 am
The hack uses MMC5 already.
I guess mapper 12 wasn't good enough of a choice at all.
Your ROM is outdated + not allowed to post ROMs at all.

The screenshot looks like it was taken from an emulator.

Aside from that, you may want to post pictures of your cart/work and double check if all connections are correct.
download/file.php?id=4610

Please tell me, did you build this circuit?

lidnariq
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Location: Seattle

Re: iNES Mapper 12 (MMC3A?)

Post by lidnariq » Sat May 16, 2020 11:35 am

If it looks the same as though your extra hardware were entirely missing ... than somehow, electrically, your extra hardware is acting as though it were entirely missing.

Ice Man
Posts: 526
Joined: Fri Jul 04, 2014 2:34 pm

Re: iNES Mapper 12 (MMC3A?)

Post by Ice Man » Sat May 16, 2020 11:35 am

Yes, I used the circuit on Dragon Ball 5 by Rex Soft and it works perfectly fine.
Your issue is the AX5202P. The circuit can only be build on original MMC3A hardware.

Why?

All MMC3A's and non-Sharp MMC3B's will generate only a single IRQ when $C000 is $00. This is because this version of the MMC3 generates IRQs when the scanline counter is decremented to 0. In addition, writing to $C001 with $C000 still at $00 will result in another single IRQ being generated. In the community, this is known as the "alternate" or "old" behavior.

lidnariq
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Location: Seattle

Re: iNES Mapper 12 (MMC3A?)

Post by lidnariq » Sat May 16, 2020 11:40 am

The wrong IRQ behavior should cause a crash, not wrong graphics.

Ice Man
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Re: iNES Mapper 12 (MMC3A?)

Post by Ice Man » Sat May 16, 2020 11:42 am

True, but still mentioning this because any other MMC3 didn't work at all for me.
I'm not sure how AX5202P handles things.

Ruslansh
Posts: 42
Joined: Sun Apr 28, 2013 3:27 am

Re: iNES Mapper 12 (MMC3A?)

Post by Ruslansh » Sat May 16, 2020 11:42 am

Thanks for the exact answer. Honestly, I did not expect this to happen. Then you need to make an adapter for the original mapper

Ruslansh
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Joined: Sun Apr 28, 2013 3:27 am

Re: iNES Mapper 12 (MMC3A?)

Post by Ruslansh » Sat May 16, 2020 11:44 am

Now I will try to record Dragon Bellz

Ruslansh
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Re: iNES Mapper 12 (MMC3A?)

Post by Ruslansh » Sat May 16, 2020 11:57 am


lidnariq
Posts: 9305
Joined: Sun Apr 13, 2008 11:12 am
Location: Seattle

Re: iNES Mapper 12 (MMC3A?)

Post by lidnariq » Sat May 16, 2020 12:03 pm

This ROM hack expects to write to the bankswitching register at $4800, whereas DBZ5 expects it at ... maybe $4020?

Rewire it so that the 74'138 doesn't connect to CPU A5, but instead to CPU A11.

Ruslansh
Posts: 42
Joined: Sun Apr 28, 2013 3:27 am

Re: iNES Mapper 12 (MMC3A?)

Post by Ruslansh » Sat May 16, 2020 12:14 pm

Thank you, I will write to the authors of the hack, maybe they can help.

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