Gadget Autopsy: The Nintendo Game Boy

Twenty years ago this month, Nintendo released the Game Boy handheld video game system in Japan. Since then, the Game Boy series of handhelds has sold over 100 million units. To celebrate its anniversary, I did what I always do: I tore one apart for the education and amusement of PC World readers.

If you enjoy this dissection, check out our other teardowns of classic technology:

— Apple IIc

— Nintendo Entertainment System

— TRS-80 Model 100

— Commodore 64

— IBM’s Model M, “The World’s Greatest Keyboard”

When Nintendo released the Game Boy in 1989, it was the first major handheld game system with interchangeable cartridges since 1979’s Milton-Bradley Microvision. The thought of playing video games anywhere–in the car, at school, in the bathroom–was mind-boggling to me at the time, and I decided that I had to have one. Within a year I was playing Tetris on the pea-green-screened portable wonder.

Like any great gaming system, the Game Boy is designed to induce anxiety. And that anxiety can create sweaty palms, which is why the Game Boy’s back has these strategically placed ridges to help you hold on even during the most stressful moments of Attack of the Killer Tomatoes. Note how snugly the cartridge fits into the slot, too.

The Super Mario Land 2 cartridge on the left contains a small lithium coin battery to supply continuous power to an SRAM chip that stores saved games. Tetris has no such save feature, so its circuit board (not shown) is much simpler.

With four AA batteries in the Game Boy, you can play for about 10 hours. That’s enough time to ensure that you’ll still be seeing Tetris’s colored blocks falling before your eyes long after you turn the device off. Compared with its competitors, the Game Boy delicately sipped battery power, which was its strongest selling point. In contrast, the colorful Atari Lynx and Sega Game Gear ate batteries faster than you could shove them in.

Enough of the outside of the Game Boy–it’s time to dive in. After removing six slightly annoying triwing screws, I carefully cracked open the unit. The Game Boy’s internals consist of two major circuit boards, seen here attached to the two halves of the device. Connecting them is a thin ribbon cable (middle) that serves as a freeway of sorts for power and I/O data.

Now that I’ve carefully unplugged the ribbon cable, you can see the two halves of the Game Boy in more detail. The top half (left) contains the LCD screen, the speaker, and the control-pad elements. The bottom half (right) holds the main motherboard, the cartridge slot, and the battery compartment.

Here I’ve removed the motherboard (right) from the back half of the Game Boy. Attached to the motherboard are two smaller circuit boards; the one at the bottom sports a headphone jack, and the other one appears to have something to do with power regulation. The shiny metal plate on the plastic case is part of the cartridge-port assembly and probably doubles as RF (radio frequency) shielding.

Here you can see the major motherboard components. The largest chip, in the center of the board, is the CPU (labeled “DMG-CPU B”). The original Game Boy used a custom Z80 microprocessor. Another interesting feature was the link port, which allowed you to connect two Game Boys with a serial cable so that you could play with (or against) your buddy in any games offering that capacity.

Here I’ve separated the circuit board bearing the unit’s LCD screen from the front of the Game Boy case. The round black thing (lower right) is the speaker. You can also see the back side of the Game Boy’s silicone control pads, which sit beneath the plastic buttons that you push to play a game.

The Game Boy’s control mechanisms work identically to those of nearly every post-NES digital game pad. Pieces of springy, flexible silicone rubber with conductive pads (blue and white items, bottom) are sandwiched between the hard plastic buttons that you push on the surface and the circuit board underneath. When you press the buttons, they push the rubber pads down to touch black contacts on the circuit board, acting as a momentary switch. In the case of the Game Boy’s Start and Select controls, the buttons you push (dark brown piece, upper right) are the silicone pads themselves.

Here we have an array of major Game Boy components: two plastic halves, a battery door, four circuit boards, and the control apparatus. It’s actually a pretty simple construction, which has no doubt contributed to the handheld’s longevity in the field. I’ve had at least two friends drop their Game Boys in the toilet, and the units lived to play Tetris another day. (One of my friends, however, confesses that his Game Boy’s life ended when he fiercely headbutted it out of frustration.)

Now I need to put everything back together. I must admit that when I first dissected a Game Boy, at age 12, I had difficulty reassembling it. A quick visit to my father’s workbench rectified the situation–he was good at that sort of thing. This time I have to do it on my own, so wish me luck.