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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.

enter image description here enter image description here

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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