Input devices

The NES has two general-purpose controller ports on the front of the console, as well as a (rarely used) 48-pin expansion port underneath.

The Famicom's standard controllers are hardwired to the front of the unit, and a special 15-pin expansion port is commonly used for third-party controllers. The AV Famicom, however, features detachable controllers using the same ports as the NES.

The NES and Famicom have a set of I/O ports used for controllers and other peripherals, consisting of the following:

• One output port, 3 bits wide, accessible by writing the bottom 3 bits of $4016.
  • The values latched by $4016/write appear on the OUT0-OUT2 output pins of the 2A03/07, where OUT0 is routed to the controller ports and OUT0-OUT2 to the expansion port on the NES.
• Two input ports, each 5 bits wide, accessible by reading the bottom 5 bits of $4016 and $4017. Reading $4016 and $4017 activates the /OE1 and /OE2 signals, respectively, which are routed to the controller ports and the expansion port.
  • On the NES, only D0, D3, and D4 are connected to both controller ports, while all of D0-D4 are connected to the expansion port.
  • On the original Famicom, the two ports differ: $4016 D0 and D2 and $4017 D0 are permanently connected to both controllers, while $4016 D1 and all of $4017's D0-D4 are connected to the expansion port.
  • On the AV Famicom, only D0 is connected to the controller ports. The expansion port is unchanged.

Programmer's reference

• Registers

Hardware

• Controller port pinout
• Controllers
  • Arkanoid controller
  • Bandai Hyper Shot
  • Coconuts Pachinko
  • Doremikko Keyboard
  • Exciting Boxing Punching Bag
  • Family BASIC Keyboard
  • Four Score/NES Satellite four-player adapters
  • Jissen Mahjong controller
  • Konami Hyper Shot
  • Miracle Piano
  • Mouse (SNES Mouse, Subor Mouse)
  • Oeka Kids tablet
  • Partytap
  • Power Glove
  • Power Pad
  • RacerMate Bicycle
  • Standard controller
  • U-Force
  • Zapper lightgun

Other I/O devices

• Famicom 3D glasses
• Family BASIC Data Recorder
• R. O. B.
• Battle Box
• Turbo File
• Barcode Battler

Usage of port pins by hardware type

Device	$4016 D4	$4016 D3	$4016 D2	$4016 D1	$4016 D0	$4016 CLK	$4017 D4	$4017 D3	$4017 D2	$4017 D1	$4017 D0	$4017 CLK	OUT2	OUT1	OUT0	/IRQ	AUDIO	+5V	GND	Note
Joypad1					x	x									x			x	x	*AUDIO line can be used for pad which has audio jack to plug in headphones (for example: IQ502 joypad) *$4016 D2 can be uses as microphone input
Joypad2			x								x	x			x			x	x
Joypad3 (Famicom)				x		x									x			x	x
Joypad4 (Famicom)										x		x			x			x	x
Lightgun Zapper (NES P2/Famicom)							x	x										x	x	*AUDIO line can be used for emiting bullet shoot sounds (for example: Casel Zapper)
Lightgun Zapper (NES P1)	x	x																x	x
Family BASIC Keyboard/Subor Keyboard							x	x	x	x			x	x	x			x	x