Nintendo Entertainment System
  | |
| |
| Top: NES Control Deck (NES-001) Bottom: Family Computer (HVC-001) | |
| Specifications | |
|---|---|
| Developer | Nintendo R&D2 |
| Manufacturer | Nintendo |
| Type | Home video game console |
| Released | 15 July 1983 (Japan) 18 October 1985 (North America) 1 September 1986 (Europe) 1987 (Australia) |
| Discontinued | 25 September 2003 (Japan) 14 August 1995 (North America) 1995 (Europe) |
| CPU | Ricoh RP2A03 (NTSC) / RP2A07 (PAL), 6502 core with on-chip sound, 1.789773 MHz (NTSC) / 1.662607 MHz (PAL) |
| Memory | 2 KB work RAM, 2 KB video RAM; cartridges may add more |
| Storage | ROM cartridge, with bank-switching mappers extending the address space |
| Display | 256×240; 64-entry palette, up to 25 colours on screen |
| Sound | 5 channels in the CPU (2 pulse, triangle, noise, DPCM); Famicom cartridges may add expansion audio |
| Graphics | Ricoh RP2C02 (NTSC) / RP2C07 (PAL) PPU; 64 sprites, 8 per scanline |
| Power | NES: NES-002, 9 V AC. Famicom: HVC-002, 10 V DC |
| OS / Firmware | None |
| Predecessor | Color TV-Game series |
| Successor | Super NES / Super Famicom |
| Model no. | NES-001 (front loader), NES-101 (top loader), HVC-001 (Famicom), HVC-101 (AV Famicom) |
The Nintendo Entertainment System (NES) is Nintendo's 8-bit home console, sold in Japan as the Family Computer (Famicom). The Famicom was released in Japan on 15 July 1983. The NES followed in North America on 18 October 1985, in Europe in 1986 and in Australia in 1987. Production ended in North America in 1995 and in Japan in 2003.[1]
For repair and servicing, start with Nintendo Entertainment System General Maintenance. The Famicom has a different board, a different power supply and its own pages: Nintendo Famicom General Maintenance, Nintendo Famicom Troubleshooting Guide and Nintendo Famicom Capacitor Replacement Guide.
Architecture
[edit | edit source]The CPU is the Ricoh RP2A03 on NTSC machines and the RP2A07 on PAL machines: a 6502 core with the sound generator and the controller read and strobe lines on the same chip. The CPU takes the master clock on pin 29 and divides it by 12 on the RP2A03 and by 16 on the RP2A07, giving 1.789773 MHz and 1.662607 MHz.[2]
The master clock is 21.47727 MHz on NTSC machines and 26.601712 MHz on PAL machines.[3] On the NES-001 it comes from crystal X1 and oscillator transistor Q2, which Nintendo calls the system timing section.[4][5]
Memory
[edit | edit source]The NES-001 has 2 KB of work RAM at U1 and 2 KB of video RAM at U4, each a 2K×8 static RAM.[6] Cartridges add their own ROM, often with a mapper chip to bank-switch it, and sometimes RAM. Games that save keep the save in battery-backed RAM in the cartridge; the console has no battery.[7]
Graphics
[edit | edit source]The RP2C02 picture processing unit (RP2C07 on PAL machines) draws a 256×240 picture from background tiles and up to 64 sprites, at most 8 of them on one scanline. The palette has 64 entries, some of them duplicates. The palette RAM holds four background and four sprite palettes of three colours each plus one shared backdrop colour, so no more than 25 colours can be on screen at once.[3]
Sound
[edit | edit source]The sound generator is inside the CPU: two pulse channels, a triangle, a noise channel and a delta-modulation channel for samples. The pulse channels leave the CPU on pin 1 (AD1) and the others on pin 2 (AD2).[2] There is no separate sound chip.
Input, output and expansion
[edit | edit source]The NES has two detachable controller ports. The Famicom's two controllers are wired in, but each plugs into the board on a connector, and Nintendo's Famicom service manual treats a controller cord or board as a replaceable part; controller 2 carries a microphone.[8] The button shift register, a 4021, is inside each controller.[9][8]
The NES cartridge connector has 72 pins and the Famicom's 60. On the NES-001, pin 36 is +5 V and pin 72 ground.[6][10] The Famicom has a 15-pin D-sub expansion socket.[8]
Power
[edit | edit source]| Machine | Adapter | Output | Notes |
|---|---|---|---|
| NES-001 and NES-101 | NES-002 | 9 V AC, 1.3 A | The console rectifies and regulates it. On the NES-001 the supply section is in the RF modulator module; on the NES-101 the 7805 is on the mainboard |
| Famicom (HVC-001) | HVC-002 | 10 V DC | Nintendo gives 13.5 ± 1.5 V DC with no load as normal. The power section, with a 7805 taking 13-14 V in and giving 5 V out, is in the RF modulator unit |
Sources: the NES-002 rating plate, Nintendo's NES workbook and Famicom service manual, and Console5.[11][5][8][12] The logic on both machines runs from a single +5 V rail.
Servicing
[edit | edit source]| Topic | Page |
|---|---|
| NES preventive care, chip map, test points | Nintendo Entertainment System General Maintenance |
| NES fault-finding, including Nintendo's fault table | Nintendo Entertainment System Troubleshooting Guide |
| NES capacitors, by module | Nintendo Entertainment System Capacitor Replacement Guide |
| Famicom preventive care | Nintendo Famicom General Maintenance |
| Famicom fault-finding | Nintendo Famicom Troubleshooting Guide |
| Famicom capacitors | Nintendo Famicom Capacitor Replacement Guide |
Documentation
[edit | edit source]- NOA Independent Servicer Technical Training Workbook: Nintendo of America's technician workbook (Rev. 11/90), with the control deck fault table, test procedure, schematic and waveforms.
- Nintendo World Class Service NES Product Maintenance Troubleshooting And Service Guide: Nintendo's consumer maintenance and troubleshooting leaflet.
- Nintendo Famicom Service Manual: Nintendo's 1992 Japanese service manual for the Famicom, Super Famicom and Game Boy.
- NES-001 Schematic: a 2020 redraw of the NES-001 mainboard.
- NES Schematics: a 1989 schematic set of unrecorded origin covering the NES mainboard and five cartridge boards.
Mainboards
[edit | edit source]-
NES-001 (front loader) mainboard, NES-CPU-07 -
NES-101 (top loader) mainboard, NESN-CPU-01 -
Famicom mainboard
Schematic drawings
[edit | edit source]-
Cartridge, controller and Zapper -
Controller ports -
CPU, PPU, RAM and CIC -
Power, AV and RF switch
These four drawings are Electronix Corp.'s NES-001 schematics, as published by Console5.[6]
Gallery
[edit | edit source]-
Nintendo Entertainment System with controller -
Family Computer (Famicom) -
NES controller -
Famicom controller I -
Famicom controller II, with microphone
Related pages
[edit | edit source]References
[edit | edit source]- ↑ Wikipedia, "Nintendo Entertainment System" (retrieved 2026-10-01). Tertiary source for release and discontinuation dates and the developer.
- ↑ 2.0 2.1 NESdev Wiki, "CPU pinout" (retrieved 2026-10-01). RP2A03 pin assignments, the clock division by 12 (NTSC) or 16 (PAL), and the audio outputs on pins 1 and 2.
- ↑ 3.0 3.1 NESdev Wiki, "PPU variants" and "PPU palettes" (retrieved 2026-10-01). NTSC and PAL master clocks, the RP2C02 and RP2C07, the 64-entry palette and the 32-byte palette RAM.
- ↑ N. Schenk (Schenktronics), NES Schematics, file Original_NES.sch, rev. 1.0, 2020-06-05. Hosted as NES-001 Schematic (PDF). Clock generator: X1 21.47727 MHz with Q2 and Q3.
- ↑ 5.0 5.1 Nintendo of America, World Class Service Authorized Servicer Technical Training Workbook (running header "NOA Independent Servicer Technical Training Workbook", Rev. 11/90). Hosted as NOA Independent Servicer Technical Training Workbook. System overview, p. 6; Appendix B control deck schematic (PDF pages 93-94) and section descriptions (PDF page 97).
- ↑ 6.0 6.1 6.2 Console5 TechWiki, "Nintendo NES-001" (retrieved 2026-10-01). Chip map, capacitor lists and test points.
- ↑ Nintendo of America, World Class Service Authorized Servicer Technical Training Workbook, Rev. 11/90, p. 44, "NES Game Pak Operation": game paks hold up to three memory ICs, and in some games the work RAM is connected to a battery to keep its contents.
- ↑ 8.0 8.1 8.2 8.3 Nintendo, ファミコン・スーパーファミコン・ゲームボーイ サービスマニュアル (Famicom, Super Famicom and Game Boy service manual), issued 7 August 1992. Hosted as Nintendo Famicom Service Manual. HVC section, pp. 2-10: p. 2, layout and faults by unit, AC adapter DC 10 V and DC 13.5 ± 1.5 V with no load, power section in the RF modulator; p. 6, power circuit (7805, 13-14 V in, 5 V out); p. 10, Famicom repair price list.
- ↑ NESdev Wiki, "Standard controller" (retrieved 2026-10-01).
- ↑ NES Schematics, 1989 CAD schematic set, sheet 1 (NESMB1.SCH, rev. A, 12 July 1989), author not recorded. Hosted as NES Schematics (PDF).
- ↑ Evan-Amos, "Nintendo-Entertainment-System-NES-Power-Supply.jpg", Wikimedia Commons, public domain. Rating plate: "Output AC9V 1.3A", "for use with NES Control Deck No. NES-001 & NES-101 only".
- ↑ Console5 TechWiki, "Nintendo NES-101" (retrieved 2026-10-01).
