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I stumbled upon screenshots of the Tiger Game.Com handheld running its Resident Evil 2 port and I'm curious to know what its graphical capabilities actually are:

https://twitter.com/_Kimimi/status/1357724774500360192 (from: https://twitter.com/_Kimimi/status/1357724774500360192)

It seems to be capable of very large sprites and backgrounds which don't feature any obvious tiling. I would guess that perhaps it has a framebuffer which is filled in by its CPU (which at 200x160, 10MHz while also handling audio and gameplay logic, would explain the slow frame rate) but I haven't been able to find any articles which describe any hardware accelerated graphics such as the Game Boy's tiling background or OAM sprites. Does anybody know if the handheld featured any?

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The Game.com doesn't support sprites or tilemaps. It has a flat, memory-mapped bitmap display with internal support for accelerated optionally-masked and/or X/Y flipped rectangle blits.

From what I can tell, the Tiger Game.com is basically a Sharp SM8521 "Single Chip Microcomputer" (datasheet) with a touchscreen display added on. That chip has two internal 8k byte VRAM banks of 200x160 pixels with 2 bits per pixel. I believe the currently displayed bank can be toggled for double buffering.

On pages 35 and 36, the datasheet describes a DMA mode internal to the chip that allows it to perform rectangle masked blits from ROM to VRAM, or VRAM to VRAM.

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Page 39 describes a method of horizontally flipping data during a blit. Vertical flipping can be achieved by setting a negative Y increment.

There's also some other stuff there about 'gradations' which seems to be a kind of palette transformation during a copy, but I don't understand that.

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