Strange cartridge
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- krzysiobal
- Posts: 1037
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Strange cartridge
What's that? Even no CHR chip?
My website: http://krzysiobal.com | My NES/FC flashcart: http://krzysiocart.com
Re: Strange cartridge
Could it be a prototype Game Genie?
In the Game Genie patent, the first diagrams are of a double-ended cartridge with six 16-position dials on it, presumably a manual way of entering a 6-letter Game Genie code.
The Game Genie has no CHR ROM, it generates sixteen different "chunky pixel" tile patterns based on the CHR address requested, this method is also mentioned in the patent.
In the Game Genie patent, the first diagrams are of a double-ended cartridge with six 16-position dials on it, presumably a manual way of entering a 6-letter Game Genie code.
The Game Genie has no CHR ROM, it generates sixteen different "chunky pixel" tile patterns based on the CHR address requested, this method is also mentioned in the patent.
- krzysiobal
- Posts: 1037
- Joined: Sun Jun 12, 2011 12:06 pm
- Location: Poland
- Contact:
Re: Strange cartridge
Hmm, looking at this poor quality picture I see the CHR pins are not connected to anything at all.
So I assume either the cartridge does not display anything or.. uses console internal VRAM as chr-ram ?
So I assume either the cartridge does not display anything or.. uses console internal VRAM as chr-ram ?
My website: http://krzysiobal.com | My NES/FC flashcart: http://krzysiocart.com
Re: Strange cartridge
Game Genie appears to make a makeshift CHR ROM out of a multiplexer selected by A2 on the PPU bus. In the top half of each character (A2=0), the circuit generates D7-D4 and D3-D0 from two bits in the address, and in the bottom half (A2=1), it generates D7-D4 and D3-D0 from two other bits.
Re: Strange cartridge
This is a karaoke cartridge for one of the FC machines (called learning machines in China) made in China.
I don't know what model it is.What is certain is that VRAM is built into the machine, similar to SUBOR 97.
I got this cartridge once.And mapping schematic diagram, save ROM data.I'll post it here if you want.
Cartridges of interest.
viewtopic.php?t=18248&start=15
I don't know what model it is.What is certain is that VRAM is built into the machine, similar to SUBOR 97.
I got this cartridge once.And mapping schematic diagram, save ROM data.I'll post it here if you want.
Cartridges of interest.
viewtopic.php?t=18248&start=15