Question about "Full Graphics Function"

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Ralakimus
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Question about "Full Graphics Function"

Postby Ralakimus » Mon Apr 03, 2017 3:24 pm

While reading through the documentation, I noticed there was a "Full Graphics Function" for the ASIC chip that allows you to input a bitmap from the MCD side and the MD side can read it as tiles, while in 1M/1M mode.

I'm not quite sure how I could perform this. Is it just that you put in the data and it automatically does the job or is there a certain thing you got to do to activate it?

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Orion_
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Re: Question about "Full Graphics Function"

Postby Orion_ » Wed Apr 19, 2017 4:24 pm

you just have to write data at a specific address on the CD side
and read back the "tiled" data on the MD side

depending on the way your tile map is set up on the MD side
For example, for a 64x16 TileMap Mode (512x128 pixels screen)
write your data to WordRAM at $D0000 from CD cpu side
and read them back at $230000 from MD cpu side (using DMA transfer to VRAM it's faster)

nothing to wait, (beside waiting for the CD cpu to write all the data to the wordram)
Retro game programming !

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Ralakimus
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Re: Question about "Full Graphics Function"

Postby Ralakimus » Wed Apr 19, 2017 10:29 pm

Ah, so it's as simple as that. Thanks!


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