NES Hardware re-implimentation on a PCI card.

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NES Hardware re-implimentation on a PCI card.
by on (#110048)
I have experience with electronics and hardware, mainly with the C64 and Apple ][ scene. There is a board called the C-One reconfigurable computer. It is basically a motherboard with empty sockets on it + additional hardware allowing a person to use the original chips off 6502 based computers. The purpose is to keep its original hardware capabilities/compatibility and enhance it with new features expending what can be done.

This got me thinking, what if the same could be done for the NES? Possibly even a PCI card or USB. The idea would be to have a PCI card in a modern day Computer that could allow a person to run NES games through an application that communicates directly with the hardware without the use of emulation. This would be a lot like a Development board used for the N64 in SGI computers. A Cartridge slot could be added to one of the 5.25" Drive bays and the games could be loaded from there, or directly from the computer. Obviously for the computer loading aspect to work, it would need to emulate the different mappers, but other than that, everything would be running natively.

The planned approach would be to use an FPGA-PCI board with address lines connected to an NES board and attempt to have it communicate directly with the system. Easiest approach may be to replace the NES CPU altogether since all the opcodes on a 6502/6510 are well documented, and all the hardware on the NES connects to it. This would allow for some rather interesting possibilities in terms of being able to address more memory or operate at higher clock speeds.

I remember there was someone working on cloning the PPU of the NES to allow for RGB video without sacrificing a PlayChoice 10. The work from that could be used for capturing the video data from the hardware without the use of a video capture card. Without out it though, the rest of this is still possible, the video output would just be on another screen.

Has anyone thought of this before or tried? I am tempted to start on it myself, just figured I'd see if anyone has any useful info on interfacing with an NES.
Re: NES Hardware re-implimentation on a PCI card.
by on (#110060)
NES (well, PPU) daughtercards have been done before (BriPro's ISA bridge, Kevtris's debug "for the lulz" PPU in his nandputer)...

I thought the really cool thing about the c-one is that it is standalone? By now, it seems to me that putting a 2A03/2C02 in a desktop machine makes about as much sense as putting a 6507/Stella in one...
Re: NES Hardware re-implimentation on a PCI card.
by on (#110065)
lidnariq wrote:
NES (well, PPU) daughtercards have been done before (BriPro's ISA bridge, Kevtris's debug "for the lulz" PPU in his nandputer)...

I thought the really cool thing about the c-one is that it is a standalone? By now, it seems to me that putting a 2A03/2C02 in a desktop machine makes about as much sense as putting a 6507/Stella in one...


The NES is already a stand alone computer/console. I'm not trying just stick a 2C02 chip in a PC, that has already been done. The point of pairing it up with another computer would be to do things you normally couldn't with just the stock hardware alone. One could argue that the SGI Ultra 64 board was pointless and stupid because you could just use an N64 instead and keep reflashing a cartridge going back and forth between a development computer and the system.

To the best of my knowledge, I have not seen anything that allows a person to have full debugging capabilities on the actual hardware seeing what is in memory and what is happening at any given point and send commands to the system in real time. I guess the closest is the CopyNES board which gets installed in an NES and then connected via USB.
Re: NES Hardware re-implimentation on a PCI card.
by on (#110066)
Oh, a fully-hosted debugger? Yeah, that'd be pretty cool. Aspects of that are in NESICIDE (emulated), CopyNES, and I thought I'd read that they were putting that into the Invitenes flash cart.