Nintendo 64

The Nintendo 64 launched with Super Mario 64, which redefined 3D platforming. The console’s custom silicon—developed with Silicon Graphics—provided capabilities competitors couldn’t match, though cartridge media limited storage. Four built-in controller ports made local multiplayer fundamental rather than optional. GoldenEye, Mario Kart 64, and Super Smash Bros. became legendary party games.

Fast facts

Manufacturer: Nintendo.
CPU: MIPS R4300 — which never addresses main memory directly.
RCP: Reality Coprocessor — memory controller, renderer and sound, in one chip.
RAM: 4MB (expandable to 8MB with Expansion Pak).
Media: cartridge (8-64MB typical).
Controllers: four ports standard.

One chip in the middle of everything

Nintendo’s Ultra 64 Programming Manual opens its hardware chapter with a sentence that reorganises the machine:

The RCP is the center of the game; all data must pass through it. It acts as the memory controller for the CPU.

The R4300 does not address RDRAM. What sits on the other side of the processor’s bus is the Reality Coprocessor, and memory is on the far side of that. Every other N64 component is described in relation to the same chip: “Attached to the RCP are memory chips, the MIPS R4300 CPU, and some miscellaneous I/O chips.”

And there is only one memory:

The display portion of the RCP renders into the graphics framebuffer located in main memory. The video and audio portions of the RCP, DMA framebuffer, and audio data from main memory to drive the video and audio DACs.

The framebuffer is in main memory. Scanout reads it from main memory. Audio is DMA’d from main memory. So the CPU, the renderer, the video output and the sound are all drawing on one pool at once.

This is the oldest problem in this Vault arriving at its last form. The ZX81 had no video hardware and gave the processor’s time to the screen. The C64 loses 43 cycles in 63 on a bad line. The Amiga can lose every slot to bitplane DMA. The Mega Drive stops the 68000 for DMA but lets the Z80 run. Fifteen years later the contention has not gone away — it has been centralised into a single chip and given a name.

The graphics pipeline is a program you choose

The most consequential thing in the manual is that the N64’s geometry stage is not fixed function. The RSP runs microcode, and Nintendo shipped several:

There are three different versions of RSP geometry microcode: gspFast3D, gspLine3D, and gspTurbo3D.

Elsewhere the list runs to six — gspFast3D, gspF2DNoN, gspLine3D, gspTurbo3D, gspSuper3D, gspSprite2D — and they are not interchangeable. gspFast3D is “the optimized, full-featured 3D polygonal geometry microcode”. gspTurbo3D buys speed by giving things up, and the manual lists exactly what:

The features not supported by gspTurbo3D are: Clipping, lighting, perspective-corrected textures, and matrix stack operations. The quality of the anti-aliasing also suffers, due to the lack of precision … This loss of precision can also manifest itself as various visual artifacts, depending on the content.

gspSuper3D likewise “does not support perspective corrected” textures. So two N64 games can differ in whether their hardware does perspective correction at all, because that was a build-time choice by the developer rather than a property of the console.

The routing was a choice too. The RSP could feed the rasteriser directly, or write its commands to memory for later — which Nintendo suggests using to run the two halves of the chip on different jobs: “you could use the RSP for audio processing while the RDP is processing commands stored in DRAM.”

Developing on a workstation, again

The press reported that Nintendo’s studios were working on Silicon Graphics machines. The manual gives the arrangement:

The ROM cartridge is replaced by 16 megabytes of RAM, called the ramrom, that is accessible from both the Indy workstation over the GIO bus

Sixteen megabytes standing in for the cartridge — four times the console’s own main memory — and doubling as the debugger’s channel. The N64’s architecture is a workstation graphics pipeline scaled down, which is the reason a programmable geometry stage existed on a games console in 1996 at all.

The cartridge decision, argued at the time

The entry’s “cartridge retention: no load times, higher cost” is the settled verdict. The press of 1995 was not settled about it at all, and Edge recorded two specific costs that are easy to lose in hindsight.

Nintendo capped the size of launch games. Not the hardware — Nintendo:

Nintendo’s insistence that the first games developed for the Ultra 64 be no larger than 100 megabits before compression — a requirement that is causing considerable problems for eager programmers and designers.

One hundred megabits is twelve and a half megabytes, against a CD’s 650. A developer quoted a few months later set the price of that format against the only real precedent: “The Neo-Geo … had 100 megabit carts available for it, and they were very expensive” — the Neo Geo being the machine whose cartridges cost more than the console.

Developers had no machine to develop on. With no target hardware, Nintendo’s studios worked on Silicon Graphics workstations that did not match the console:

In the absence of an Ultra 64 target box, Nintendo’s developers have to get to grips with a Silicon Graphics Onyx … The current development hardware is way out of scope with the final spec.

The workaround was to disable Onyx features to approximate the weaker console, and one developer told Edge it was not working: “What they are switching off in the Onyx isn’t enough.”

Edge did allow the decision one merit, and it is the argument Nintendo’s defenders still make: cartridges meant “developers will be forced to concentrate on game engines and playability rather than trying to fill CDs”.

Britain paid £250, then £150

The machine was late — announced as Project Reality, renamed Ultra 64, then Nintendo 64, and delayed repeatedly enough that Edge 22 ran “Nintendo’s Ultra 64 delayed” as a cover line in July 1995.

Britain got it on 1 March 1997, and N64 Magazine’s first issue put the price plainly: “Even at a bank-account-evacuating £250, the N64 is worth every penny.”

By its third issue, three months later, the same magazine was reporting “the slashing of the Nintendo 64’s price from £250 to £150”. It also recorded what made the original figure sting: N64s “were selling in Japan and the US for around £120”, and even allowing that “electronics goods are always more expensive in the UK”, the expected price had been £200.

A hundred pounds off inside three months is not a promotion; it is a correction.

Technical approach

N64’s design philosophy:

Cartridge retention: no load times, higher cost.
Anti-aliasing: built-in edge smoothing.
Texture filtering: reduced pixelation.
Memory expansion: Expansion Pak for enhanced games.

Multiplayer legacy

Four-player console gaming:

GoldenEye 007: split-screen FPS battles.
Mario Kart 64: racing rivalry.
Super Smash Bros.: fighting party game.
Mario Party: board game chaos.

Four controllers, infinite memories