COOLBOY cartridges - ultracheap selfmade Famicom multicart

Discuss hardware-related topics, such as development cartridges, CopyNES, PowerPak, EPROMs, or whatever.

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lidnariq
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by lidnariq »

I just started translating the source code into wiki notes. Come back in an hour or two.

Edit: done.
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Cluster
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by Cluster »

you MUST enable writes to the MMC3's PRG RAM to write to these registers
Actually it's not true. You can disable PRG RAM and write to $6000-$6003.
So you can keep you games saves safe while using loader.
lidnariq
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by lidnariq »

Oh, I misread the conditional in FCEUX's source. → fixing
tepples
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by tepples »

Cluster wrote:So you can keep you games saves safe while using loader.
Saves, plural? Or will other games that use RAM overwrite your save? Is RAM even present on most carts? And won't writes to RAM trigger the lockout by accident?
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Cluster
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by Cluster »

tepples wrote:
Cluster wrote:So you can keep you games saves safe while using loader.
Saves, plural? Or will other games that use RAM overwrite your save? Is RAM even present on most carts? And won't writes to RAM trigger the lockout by accident?
Other games will overwrite save, yes :( I wrote "saves" bacause usually game using several save slots. My english is not so good, sorry :(
lidnariq
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by lidnariq »

tepples wrote:And won't writes to RAM trigger the lockout by accident?
That's clearly intentional: the mapper was designed for a multicart of games, so the menu "should" have already triggered the lockout as it starts the game.

Given that the control registers are present over the entire PRG RAM area, PRG RAM isn't really usable without having triggered the lockout anyway.
Edizius
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by Edizius »

Hi all,
Sorry to reactivate this old thread, but I think it is very cool and interesting.

I have a question concerning the modification: If one uses a NES to SNES converter (e.g. RetroPort), is it then possible to install SNES roms on the chip and have a cheap SNES-game-compilation? I know one is 8bit the other one 16 bit ROMs, but for the Microprocessor this should make no difference, right?

From pin-point of view i think SNES has 62 pins instead of 72 pins on NES, so should also be fine, or?

Thanks in advance,
Best regards edizius
tepples
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by tepples »

The RetroPort is a NOAC Famiclone, with its own CPU, PPU, and APU. It draws power and input from the Super NES Control Deck, interprets the instructions in the cartridge, outputs audio and video through a connector on the side, and can additionally send video to certain cart connector pins on certain Super Famiclone models (not an authentic Super NES). I'm guessing it outputs analog audio through the same cart connector pins that the Super Game Boy uses, but I'm not sure of that.

What I do know is that it is not a straight-through pin adapter. Even if there were a pin adapter, it couldn't work for games bigger than 32K because the connector doesn't provide enough CPU address lines.

Are you thinking of the way Space Invaders for Game Boy can launch a full Super NES port of the game if used in Super Game Boy? That works by loading the ROM through the Game Boy's video output and running it from RAM. To accomplish this, the game is relinked to run from $7E0000 rather than the usual $C00000 (HiROM) or $808000 (LoROM), and the Game Boy game loads the Super NES game 4K at a time into video memory and then sends bulk transfer commands to the SGB over the link port.[1] Even if the RetroPort had a special mode for this, and I don't know if it does, it wouldn't be able to run commercial Super NES games, as games would be limited to just under 256K, the size of high WRAM (120K), VRAM (64K), and audio RAM (64K) combined, and relinked in high WRAM.

[1] "SGB VRAM Transfers" in Pan Docs
Edizius
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by Edizius »

Hi. Thanks for the fast reply. Unfortunately i read your post through several times, and i think i am either to stupid or not deep enough in the topic to understand everything, but as far as i understood, creating a custom snes rom is not feaseable with nes adapter nor with the official gameboy adapter. I hope other people coming across this thread understand more precisely what you wrote. Thanks again for your fast answer and your help.

So to create custom cartridges, best thing will be to order super everdrive or similar I guess

All the best wishes, edizius
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by Edizius »

Ok, googling "space invadors super gameboy snes" helped me to understand: this is pretty cool!!! And yes, something like that i was thinking about. Are there "snes gameboy cartridges" ? As far as I understood it, theoretically any snes game can be started via s modified space invaders cartridge, or?
tepples
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multica

Post by tepples »

Let's take the SGB discussion to a separate topic.
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Cluster
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multicart

Post by Cluster »

There is huge update of my COOLBOY Multirom Builder:
https://github.com/ClusterM/coolboy-multirom-builder

It supports both COOLBOY and MINDKIDS mappers (other submappers support planned) and up to 15 battery-backed games on self-writable cartridges!
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ne7!
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multicart

Post by ne7! »

Very cool update to the menu here Cluster, do you know if it’s possible to rewrite these carts using something like the kazzo? Be fun to give it a go over Xmas if it’s doable :)
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Cluster
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Re: COOLBOY cartridges - ultracheap selfmade Famicom multicart

Post by Cluster »

ne7! wrote: Thu Dec 22, 2022 6:17 pm Very cool update to the menu here Cluster, do you know if it’s possible to rewrite these carts using something like the kazzo? Be fun to give it a go over Xmas if it’s doable :)
It's possible if cartridge is self-writable (soldering is not required). Usually it's battery-backed cartridges from Mindkids. But you need to write script to do it.
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