SNES map DMA packets

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Oziphantom
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SNES map DMA packets

Post by Oziphantom » Wed Jul 11, 2018 3:07 am

I've been thinking about the map export. Making a simple 2D array is probably not what people need. It would be better to store lines and columns in DMA reads packets, so you can just set the DMA and go.

What address inc setup to people use for these tasks?

psycopathicteen
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Re: SNES map DMA packets

Post by psycopathicteen » Wed Jul 11, 2018 4:45 am

Horizontal uses increment by 1, verticle uses increment by 32. Both need increment when $2119 is written to.

tepples
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Re: SNES map DMA packets

Post by tepples » Wed Jul 11, 2018 5:54 am

Is this converter that emits baked DMA packets intended for use with horizontal-only or vertical-only scrolling? Because if you're doing more than 2-way scrolling, these packets are going to be redundant at best, storing both vertical and horizontal copies of the same map. At worst, they'll be useless, as a vertical update to a 64x32 map has to wrap around the seam.

Oziphantom
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Re: SNES map DMA packets

Post by Oziphantom » Wed Jul 11, 2018 6:31 am

well you can have limited 8way, in that it fits within the 2 screens -super mario 3, raiden style etc

it wouldn't be the only way to export data, just might be something else nice to have.

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