DK JR Math repro issue

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ironsniper1
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DK JR Math repro issue

Post by ironsniper1 » Sun Mar 21, 2021 8:50 am

hey everyone, I am trying to make myself a repro of dkjr math to round off my black box collection, the issue is when you play the game the pause menu is on the main menu, every other part of the game seems to be fine except this one,

I have tried different roms and they are all the same, tried them in an emulator and they work fine so I dont know what the issue could be, I have also tried other game roms and they worked fine, if anyone has any ideas please let me know.
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Memblers
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Re: DK JR Math repro issue

Post by Memblers » Sun Mar 21, 2021 11:53 am

Possibly the mirroring jumper has the wrong setting, there's not much else that can go wrong with NROM.

ironsniper1
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Re: DK JR Math repro issue

Post by ironsniper1 » Sun Mar 21, 2021 12:09 pm

Memblers wrote:
Sun Mar 21, 2021 11:53 am
Possibly the mirroring jumper has the wrong setting, there's not much else that can go wrong with NROM.
i have it set for vertical according to this page http://bootgod.dyndns.org:7777/profile.php?id=523, but i dont see how something like that would cause the pause menu to appear over the main menu

krzysiobal
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Re: DK JR Math repro issue

Post by krzysiobal » Sun Mar 21, 2021 1:22 pm

On official NES boards:
"V" jumper closed = vertical arrangement = horiozntal mirroring
"H" jumper closed = horizontal arrangement = vertical mirroring

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poorstudenthobbyist
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Re: DK JR Math repro issue

Post by poorstudenthobbyist » Sun Mar 21, 2021 3:34 pm

What ROM chips are you using?
Check out my website for NES, SNES, and Genesis tutorials here. And visit my store for some custom tools and boards for making games here.

You can also follow me on Twitter for infrequent updates and bad jokes!

lidnariq
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Re: DK JR Math repro issue

Post by lidnariq » Sun Mar 21, 2021 3:56 pm

[Takes a copy of the ROM, edits the header to indicate the wrong mirroring, gets the exact problem you show in your picture]

Yeah, definitely "wrong nametable mirroring".
Donkey Kong Jr. Math-with-wrong-mirroring.png
Donkey Kong Jr. Math-with-wrong-mirroring.png (1.68 KiB) Viewed 1952 times

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tokumaru
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Re: DK JR Math repro issue

Post by tokumaru » Sun Mar 21, 2021 4:44 pm

I don't know who made the PCB for this cartridge, but the H and V letters used in original Nintendo boards do not mean "mirroring", they mean "arrangement". If the name tables are arranged horizontally, this means that they're vertically mirrored, and vice versa. It's fucked up, I know... blame it on the person who first came up with the iNES header.

ironsniper1
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Re: DK JR Math repro issue

Post by ironsniper1 » Sun Mar 21, 2021 5:49 pm

I removed the jumper on the pcb itself and still there, so is this a rom issue or pcb issue and which would be easier to fix? The chips are AT29C256

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Re: DK JR Math repro issue

Post by lidnariq » Sun Mar 21, 2021 5:57 pm

You need to not only desolder/cut the "H" or "V" jumper but also to resolder the other one ... although I can't quite tell what 3rd party clone board you're using, so instructions may vary.

ironsniper1
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Re: DK JR Math repro issue

Post by ironsniper1 » Sun Mar 21, 2021 6:21 pm

lidnariq wrote:
Sun Mar 21, 2021 5:57 pm
You need to not only desolder/cut the "H" or "V" jumper but also to resolder the other one ... although I can't quite tell what 3rd party clone board you're using, so instructions may vary.
https://www.muramasaentertainment.com/product/nes-nrom/

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poorstudenthobbyist
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Re: DK JR Math repro issue

Post by poorstudenthobbyist » Sun Mar 21, 2021 6:25 pm

I believe it's Muramasa's NROM board
I think you messaged me the other day about a different thing - I recognized the print on the PRG label, lol
Make sure /WE is tied to VCC as well - this might be the case already for his boards but I'd check to be sure.
Check out my website for NES, SNES, and Genesis tutorials here. And visit my store for some custom tools and boards for making games here.

You can also follow me on Twitter for infrequent updates and bad jokes!

ironsniper1
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Re: DK JR Math repro issue

Post by ironsniper1 » Sun Mar 21, 2021 6:37 pm

poorstudenthobbyist wrote:
Sun Mar 21, 2021 6:25 pm
I believe it's Muramasa's NROM board
I think you messaged me the other day about a different thing - I recognized the print on the PRG label, lol
Make sure /WE is tied to VCC as well - this might be the case already for his boards but I'd check to be sure.
your board was a very different issue, with yours i couldnt get anything to show up and with this new one everything shows up good except the main menu, also i havent gotten around to trying the fix on your board yet but just wanted to say thanks again for the help!
Image

did a continuity test on the Muramasa board and pin 1 and 28 are connected

EDIT wired pin 1 to pin 28 on the poorstudenthobbiest board and now it works but same issue as the other

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Memblers
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Re: DK JR Math repro issue

Post by Memblers » Sun Mar 21, 2021 10:52 pm

ironsniper1 wrote:
Sun Mar 21, 2021 12:09 pm
i have it set for vertical according to this page http://bootgod.dyndns.org:7777/profile.php?id=523, but i dont see how something like that would cause the pause menu to appear over the main menu
Looks like they must be pre-loading the pause screen into the other nametable. So when it pauses, they simply scroll or select the other table, instead of writing it then. And because of the mirroring being wrong, it's (over)writing it to the "main" nametable instead.

But yeah it's like krzysiobal said, depending on the board, H is vertical and V is horizontal. It's really a quirk with the way .NES file format describes it, and it trips everyone up at some point, you're not alone in that, haha.

ironsniper1
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Re: DK JR Math repro issue

Post by ironsniper1 » Mon Mar 22, 2021 12:13 am

Memblers wrote:
Sun Mar 21, 2021 10:52 pm
ironsniper1 wrote:
Sun Mar 21, 2021 12:09 pm
i have it set for vertical according to this page http://bootgod.dyndns.org:7777/profile.php?id=523, but i dont see how something like that would cause the pause menu to appear over the main menu
Looks like they must be pre-loading the pause screen into the other nametable. So when it pauses, they simply scroll or select the other table, instead of writing it then. And because of the mirroring being wrong, it's (over)writing it to the "main" nametable instead.

But yeah it's like krzysiobal said, depending on the board, H is vertical and V is horizontal. It's really a quirk with the way .NES file format describes it, and it trips everyone up at some point, you're not alone in that, haha.
wow that is confusing cause i was thinking V=vertical and H=horizontal either way its fixed now thanks to all of y'alls awesome knowledge! huge thanks!
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Image

ironsniper1
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Re: DK JR Math repro issue

Post by ironsniper1 » Tue Mar 23, 2021 9:37 am

just wanted to say thanks again for the help!
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