The abstract reads:
A software emulator for emulating a handheld video game platform such as GAME BOY.RTM., GAME BOY COLOR.RTM. and/or GAME BOY ADVANCE.RTM. on a low-capability target platform (e.g., a seat-back display for airline or train use, a personal digital assistant, a cell phone) uses a number of features and optimizations to provide high quality graphics and sound that nearly duplicates the game playing experience on the native platform. Some exemplary features include use of bit BLITing, graphics character reformatting, modeling of a native platform liquid crystal display controller using a sequential state machine, and selective skipping of frame display updates if the game play falls behind what would occur on the native platform.
And here are some choice quotes from the patent document:
 While GAME BOY.RTM. platforms are inexpensive and have long battery life, there may be situations in which it would be desirable to play or use applications developed for GAME BOY.RTM. on other platforms. For example, an airline, train or other vehicle passenger might want to play video games during a long journey. As shown in FIG. 1B, airlines are installing seat-back computer displays into the backs of airline seats. Such seat-back displays may provide a low cost personal computer including a processor, random access memory, liquid crystal display and input device(s). Similar displays could be installed in other vehicles (e.g., trains, ships, vans, cars, etc.) or in other contexts (e.g., at walk-up kiosks, within hotel rooms, etc.). It would be desirable under certain circumstances to allow users to execute all sorts of different applications including GAME BOY.RTM. video games and other applications using the general-purpose computer capabilities of such seat-back or similar display devices.
 Another challenge relates to instruction set compatibility. Nintendo’s GAME BOY.RTM. is based on an older, relatively inexpensive microprocessor (the Zilog Z80) that is no longer being used in most modern general purpose computer systems such as personal computers, seat-back displays and personal digital assistants. The Z80 instruction set (the language in which all GAME BOY.RTM. games and other GAME BOY.RTM. applications are written in) is not directly understood by the more modern Intel microprocessors (e.g., the 8086, 80286, 80386, Pentium and other processors in the Intel family) that are now widely used and found in most personal computers, seat-back displays, personal digital assistants, and the like. While it is possible to “port” certain GAME BOY.RTM. games or other applications to different microprocessor families (e.g., by cross-compiling the source code to a different target microprocessor), there may be an advantage in certain contexts to being able to play or execute the same binary images stored in GAME BOY.RTM. cartridges on target platforms other than GAME BOY.RTM..
 One way to provide a cross-platform capability is to provide a GAME BOY.RTM. software emulator on the target platform. Generally, a software emulator is a computer program that executes on a desired target platform (e.g., a seat-back display device, a personal computer or a personal digital assistant shown in FIGS. 1B-1D) and uses software to supply native platform capabilities that are missing from the target platform. For example, a software emulator may perform some or all of GAME BOY.RTM.’s specialized graphics functions in software, and may interface with whatever graphics resources are available on the target platform to display resulting images. A software emulator may translate or interpret Z80 instructions so the microprocessor of the target platform can perform the functions that GAME BOY.RTM. would perform if presented with the same instructions. The software emulator may include software code that emulates hardware capabilities within the GAME BOY.RTM. circuitry (e.g., audio and/or graphics processing) and/or translate associated GAME BOY.RTM. application requests into requests that can be handled by the hardware resources available on the target platform. For example, the target platform may include a graphics adapter and associated display that is incompatible with GAME BOY.RTM.’s graphics hardware but which can perform some of the basic graphics functions required to display GAME BOY.RTM. graphics on a display.
While this seems like a clear indication of Nintendo’s interest in porting their older titles to smartphones, Nintendo President and CEO Satoru Iwata has stated before that they have no interest in doing such a thing. Going by that train of thought, this patent could simply be a way of protecting their IPs from being ported by others through this same method.
Check out the gallery of images showing off said technology below: