Nintendo's creation of the cross-shaped pad changed gaming forever; indeed, every subsequent Nintendo game system has used the same basic shape, which has become an industry standard for gaming consoles. (The clamshell look incorporated in later designs of Game & Watch systems would also prove to be timeless.)
Was the Game & Watch a pioneer that paved the way for modern handheld technology? Maybe. The "& Watch" part of the system name referred to the platform's inclusion of a fully functional watch, featuring an alarm. That may have inspired future designers to include additional features to improve a product's selling points through multifunctionality--a forerunner of today's PDAs or BlackBerrys. Or maybe I'm overestimating the impact of the platform's simple digital watch feature.
A look at the primary board for the original Nintendo Game Boy.
Click on image to enlarge.
The Game & Watch systems had a short shelf life because the simple design made for repetitive play and somewhat unimaginative action. Understanding that the gaming audience was moving away from the Game & Watch but not from videogames (as evidenced by surging sales of the NES console), Nintendo's chief designer, Gunpei Yukoi, began brainstorming on the next phase of portable gaming.
Tapping his development experience with the Game & Watch systems, Yukoi envisioned a handheld device that would simulate the playing experience of the wildly popular NES console (marketed in Japan as the Famicom), released by Nintendo in 1983. In 1989, Yukoi's vision came to fruition with the introduction of the Nintendo Game Boy.
A look inside the original Game Boy reveals the simplicity of the design. A single chip provides most of the system processing power. On the primary board, the chip labeled DMG-CPU and featuring Nintendo markings is actually a Sharp-designed variation on the Zilog Z80 processor, but with a register set similar to Intel's 8080 microprocessor. The DMG-CPU features 256 bytes of ROM inside the CPU die and a core speed of 4.19 MHz.
The other main chips of interest are two ICs manufactured by Sharp (and, unlike the processor, bearing the Sharp brand). Both ICs are 64-kbit SRAM chips with the markings LH5264TN-L; one is used for video RAM and the other for CPU RAM.
The board also features an amplifier chip, labeled DMG-AMP IR3R40, that drives the Game Boy's internal speaker (or external headphones). Decapping did not reveal the device's manufacturer, and there were no telltale logos, artwork or text to confirm the maker; but judging by the IR3R40 nomenclature, this was most likely a Sharp part as well.