Original Post

I wondered if it would be possible to equip the FlashBoy or any other custom Virtual Boy cartridges with any special chips to enhance performance and maybe add features like additional sound channels or extra RAM.

There were many different so called “Memory Management Controllers” for the NES which added such features. Or think of special chips for the SNES like the SuperFX/2 or DSP.

I guess that such a chip could be very useful to get that extra performance to run things like Yeti3D smoothly with enabled textures, lighting and so on.

2 Replies

The expansion possibilities on the VB are huge!

There is an entire second address space the size of the ROM space (but writable) that’s also accessible on the cart connector. The backup (save-game) RAM space, underutilized in most commercial games, is also the same size. That’s 32 additional megabytes of address space on top of the maximum 16MB of ROM/FlashROM. Basically, the sky is the limit…

IMO, adding a large chunk of 16-bit-wide SRAM (for ease of interfacing) to the backup space would give a good performance increase for little cost. It would allow for large lookup tables and fast (one wait-state) executable space for, e.g. self-modifying code. It could even be used to increase space in the ROM, since code and data could be decompressed into and executed out of this space. It may even be possible to port Linux or another OS to the VB! Battery backup (so that commercial games can be saved) could be an issue, but I have some ideas about that. If new parts can’t be found, one possible source of SRAM chips could be old (Pentium era) cache modules.

Of course, as you mentioned, co-processors are also a possibility. There are some quite powerful-yet-inexpensive microcontrollers out there, but even something as simple as a PIC or AVR chip could be of use (perhaps the chip that performs the USB connectivity could pull double-duty). This topic is so large it really needs more space than this post to give it justice…

There are other concessions to expansion in the cart, too. For example, both the left and right audio signals pass through the cartridge connector on their way to the speakers. Something that either produces sound or alters the signals coming from the VSU could be added. I’ve often entertained the idea of attaching the SPC700 audio processor from an SNES to the cart bus. Although it wouldn’t fit inside the cart, you could add a connector to carry power/data to the SPC and audio back from it. (See: this page for almost all necessary details.)

I’ve given this a lot of thought (probably too much ;-)) and I would love to be part of the design process for the “FlashBoy 2” 😀

  • This reply was modified 14 years, 3 months ago by RunnerPack.
  • This reply was modified 14 years, 2 months ago by RunnerPack.

Yeah, as RunnerPack said, it’s VERY possible. My plan, if I ever get around to it, is to make a cart with an FPGA connected to basically all the lines on the cart, along with some RAM and Flash, then you could use the FPGA to map the RAM and Flash to any memory location, as well as using the FPGA to do processing.

Of course this isn’t foolproof, since the FPGA takes time to load, but you should be able to hit one of the interrupt lines to get control (though boot time would be a couple seconds longer). Also, with the VB being 5V, this limits the FPGA chip that can be used, since most modern ones won’t interface directly above 3.3V (though it’s much easier to find 3.3V RAM and Flash).

But yeah… that’d be very cool to have all kinds of possibilities, though we haven’t really maxed out the capabilities of the original hardware.

DogP

 

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