VDP

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Description

The VDP (Video Display Processor, 315-5113) is the video processor of the MegaDrive.

It's an evolution of the Master System VDP (which is an evolution of the TMS9918a video chip, see [1] for information about the Master System VDP).

It is backward compatible with the Master System one (MODE IV) but this section will only talk about the MODE V (MegaDrive mode).

Display Specification

The VDP think by CELL (a 8x8 pixel pattern).

It can output a 32x28 CELL image (256x224 pixels) or an 40x28 (320x224 pixels) one.

In PAL mode it can also output an 32x30 (256x240 pixels) or 40x30 (320x240 pixels) image.

Features

Ports

Registers

Scrolls

Palettes

Interrupts

DMA

Scrolling

Sprites

Priority

Interlace mode