Famicom

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Family Computer (or Famicom for short) is a video game console made by Nintendo and sold in Japan starting in 1983. The Nintendo Entertainment System, which Nintendo sold outside Japan a couple years later, is nearly identical in behavior with a few changes in the cords, controllers, system look. While the Famicom was made to look friendly and well matched for a Japanese household with bright colors, the NES was made to look like the "future" to get it into the homes of Americans who had been burned by the crash of the second-generation consoles in 1983-1984.

Differences from NES

  • On the original Famicom, controller 2 has no Select and Start buttons; they always return "not pressed". The AV Famicom uses standard NES controllers.
  • Controller 2 on the original Famicom has a microphone. It is missing on the AV Famicom.
  • There is a 15-pin expansion port. The light gun and other specialty controllers connect to this instead.
  • Only one specialty controller, such as the Zapper or Power Pad, may be connected at once. Even the AV Famicom isn't wired to accept specialty controllers made for the NES.
  • The original Famicom had only RF output, not the yellow and red AV output seen on the side of the front-loading NES.
  • Reset acts like a top-loading NES, not a front-loading NES: the Reset button resets only the CPU, not the PPU.
  • The "cassette" connector on the Famicom is smaller than the "Game Pak" connector on the NES. Famicom cassettes have 60 pins instead of 72. However, the pin pitch is slightly wider: 2.54 mm (0.1 in) on the Famicom vs. a nonstandard 2.50 mm on the NES.
  • No expansion port on the bottom, and no ten passthrough pins on the cassette connector.
  • No CIC.
  • The Famicom audio path goes through the cassette, allowing boards to mix the console's audio with that from a synthesizer chip.
  • The Famicom is always NTSC. PAL Famiclones are designed for compatibility with the NTSC Famicom; the clock rate preserves the ratio of PPU to CPU cycles, and the extra scanlines are added to the post-render period instead of vertical blanking so that cycle-counting mapper IRQs and cycle-timed NMI handlers continue to work.