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Tech and Homebrew => Turbo/PCE Game/Tool Development => Topic started by: rag-time4 on December 25, 2007, 07:11:06 PM

Title: Is somthing similar to Konami's VRC chips possible for HuCards?
Post by: rag-time4 on December 25, 2007, 07:11:06 PM
Some Konami games released on Famicom included custom chips that allowed for improved graphics and sound to games like Conta and Castlevania III, which had graphics and sound not found in the US versions, which were restricted to Nintendo-only chips.

I'm just curious, would it be possible to include custom chips in HuCard games, increasing the capability of the system?

wiki article here (http://en.wikipedia.org/wiki/Multi-Memory_Controller#Third-party_chips)
Title: Re: Is somthing similar to Konami's VRC chips possible for HuCards?
Post by: Kitsunexus on December 25, 2007, 07:27:23 PM
VRC6 rules. I wonder if it's possible to put the SVP into a HuCard?
Title: Re: Is somthing similar to Konami's VRC chips possible for HuCards?
Post by: SignOfZeta on December 25, 2007, 11:00:46 PM
Sure you could. It simply wasn't done because it wasn't needed as badly. The Famicom is really a weak-ass system that couldn't produce graphics any better than a Colecovision without MMCs, so they were pretty much required to produce the sorts of games people expected in the mid to late 80s.

Even *with* MMCs the Famicom sucked, with sprites always flickering and breaking up.
Title: Re: Is somthing similar to Konami's VRC chips possible for HuCards?
Post by: ccovell on December 26, 2007, 03:34:56 AM
SignOfZeta, you don't know what you're talking about.   [-(

First off, even without any mappers, the Famicom is a generation ahead of the Coleco, outperforming it in terms of resolution, colours per tile, maximum colours on-screen, and total colours available.

But to the issue at hand, the Famicom is limited graphically, but it extends its PPU (graphics chip) bus to the cartridge connector, making it greatly more expandable than systems that didn't.  Unfortunately, the PCE is in the latter category.  All that the HuCard connector can access is the CPU bus, meaning the only thing extra chips in a HuCard could offer would be more ROM or RAM.  No graphic enhancement is possible.

The expansion connector is another story, though.  Devices that enhanced the graphics of the PCE would be feasible (but don't exist(?)), and sound is obviously already well-supported by the CD attachment.  But sorry, special chips inside HuCards would be useless, IMO.
Title: Re: Is somthing similar to Konami's VRC chips possible for HuCards?
Post by: Necromancer on December 26, 2007, 04:19:45 AM
If I remember correctly from when a similar topic popped up, didn't someone say that a couple of the HuCard pins are used for audio?  It obviously wouldn't negate the impossibility of graphical enhancements, but it would mean that a special chip could be useful though likely impractical.
Title: Re: Is somthing similar to Konami's VRC chips possible for HuCards?
Post by: handygrafx on January 28, 2008, 09:10:01 AM
The Famicom when it was released in 1983 was a significant step up from the Atari 5200 and ColecoVision generation, if not an entire generation beyond them.   

While it's true the Famicom/NES is very limited graphially compared to the PC-Engine and even the Sega Master System,  the various mapper chips (MMC family, VRC family, etc)  provided a significant boost in graphics, upto more or less, Master System levels of graphics, not PCE level. 

Gradius II  (using VRC4 I think) was the first game I really noticed the difference.
Title: Re: Is somthing similar to Konami's VRC chips possible for HuCards?
Post by: malducci on January 28, 2008, 12:55:23 PM
If I remember correctly from when a similar topic popped up, didn't someone say that a couple of the HuCard pins are used for audio?  It obviously wouldn't negate the impossibility of graphical enhancements, but it would mean that a special chip could be useful though likely impractical.

 Yes, there are audio input pins on the hucard card for such a thing. Like the NES, you could added whatever audio addition you wanted but.... it's only mono. Fine for drum kits, bass, snare, symbols, additional sound effect channels, etc.

 There are some other things the PCE can do that you guys have yet to hear, but will soon enough. Also, the SGX has a slightly revised audio unit - allowing higher frequency wave samples at lower CPU resource cost (figured I throw that in there, not that any SGX games took advantage of it).

Title: Re: Is somthing similar to Konami's VRC chips possible for HuCards?
Post by: nodtveidt on January 28, 2008, 02:05:38 PM
The SGX wasn't supported long enough for coders to really take advantage of it.