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ricardoquesada / vchar64

editor for the Commodore 64
http://retro.moe/tag/vchar64/
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Support for C-16 & Plus/4 multicolor characters #9

Open spektro opened 8 years ago

spektro commented 8 years ago

Hi, I've been looking for a character/tile editor for creating graphics for the Commodore 16 & Plus/4 and I was wondering if VChar64 could be expanded so that it can be used for that purpose.

The C64 and C16 & Plus/4 character screen modes are identical but the C16/Plus4 interprets the color information differently. While the C64 uses 4 bits for a character color, C16/Plus4 uses 7 bits.

The color information is coded like this in the color RAM: bits 0-3 = colour bits 4-6 = luminance bit 7 = flash on/off

The same coding is used for the background colors, except bit 7 is unused.

ricardoquesada commented 8 years ago

I have no experience in C16, but if the only thing that changes is that colores are stored in 8-bit instead of 4-bit, I guess it shouldn't be difficult to support them. I'll keep this in mind for the next refactor.

spektro commented 8 years ago

Thanks! The C-16 & Plus/4 colour palette colours are presented in this Wikipedia article: List of 8-bit computer hardware palettes

If you need help testing the VChar64's C-16 & Plus/4 extension, I can help you on that.