Epoch Game Pocket Computer

The Epoch Game Pocket Computer (ゲームポケコン) is a second-generation handheld game console released by Epoch Co. in Japan in 1984 for 12,800 Japanese yen. It is also known as Pokekon and was the first handheld console to feature interchangeable cartridges, preceding the Game Boy by 5 years.

The system was a commercial failure in Japan, and as a result, only 5 games were made for it. A puzzle game and a paint program were built into the system. It was powered by 4 AA batteries, and screen's contrast could be adjusted by the user. Input and output controls included four buttons, an 8-way joypad, a contrast dial, and a sound on-off switch.

Technical specifications

 * LC display: monochrome, 75 × 64 pixels
 * Power supply: 4 AA batteries
 * Battery life: Not clear; >70 hours or 60 hours
 * CPU: NEC μPD78C06 clocked at 6 MHz
 * RAM: 2 KB
 * ROM (cartridges): 8 or 16 KB
 * Sound: 1 sound channel
 * Sound: 1 sound channel

Games
There were a total of 7 different games released for the system.

2 were built into the system. The Built-in Functions (本体内蔵機能) cartridge included with the system only serves as instructions and to occupy the cartridge slot, containing no game data, as it doesn't need to be inserted into the system to play the games; The other 5 were released separately for 2,980 Japanese yen each, excluding Pocket Computer Mahjong which was 3,800 yen;
 * Puzzle Game (パズルゲーム), an 11 tile version of Fifteen puzzle.
 * Graphics function (グラフィック機能), a Raster graphics editor paint program.
 * Astro Bomber (アストロボンバー)
 * Block Maze (ブロックメイズ)
 * Pocket Computer Mahjong (ポケコンマージャン)
 * Pocket Computer Reversi (ポケコンリバーシ)
 * Sokoban (倉庫番)