Super FX - What is the processing power of the Super Nintendo (SNES) with the special chip

English version of the text

The Super FX chip is a 16-bit RISC processor aimed at 3D. It works as a graphics accelerator, which models and renders polygons, sprites and advanced 2D effects, to a frame buffer in RAM, which it uses to later send to the Super Nes main architecture to be displayed on the game screen.

The Super Nintendo hardware, designed in the late 1980s in Japan, was a system primarily intended for generating on-screen sprites in two dimensions. At that time, 3D machines were expensive and experimental, not yet available to the public in the form of home video games.

Starglider prototype (Argonaut)

In 1989, Argonaut Games began a project to develop a special chip capable of improving the graphical and computational capabilities of the Nintendo 8-bit. According to its founder, Jez San, Argonaut intended to release this special hardware, along with a Nes version of the first-person flight simulator Starglider, developed for personal computers a few years earlier. He showed the prototype to Nintendo in 1990, and the design impressed some in Japan. So, Jez suggested that Argonaut develop a game with this special chip for the new system that Big N would soon launch, the Super Famicom. Years later, Jez would comment in an interview:

O hardware do NES

"I told them this is as good as it gets unless they let us design some hardware to make the Super Famicom better at 3D. Surprisingly, even though I had never made any hardware before, they said YES and gave me a million money to make this happen."

The Nes hardware was already outdated by the late 1980s, and could not compete with newer systems such as the Sega Genesis and TurboGrafx-16. Shortly after the 1990 Consumer Electronics Show, held in Chicago, Illinois, Argonaut ported the Nintendo version of Starglider to the Super Famicom, a process that took about a week, according to San.

Argonaut then hired a team of specialist chip designers from Cambridge to make the first 3D graphics accelerator and one of the first RISC microprocessors. The chip design team was made up of engineers Ben Cheese, Rob Macaulay and James Hakewill.

"The whole 3D acceleration market that NVidia and ATI now dominate, Argonaut got there first..." expresses Jez, "...and we have the patents to prove it."

The poorly documented Super Famicom prototype had to be reverse engineered by the team to integrate the chip into 16-bit hardware as much as possible in an effort to improve the performance of the entire system. They succeeded, but had to settle for mounting the special unit on the cartridge rather than the console. This proved to be advantageous, as it would only increase the cost of the game and not the console. The result of all this work was the "Mathematical Argonaut Rotation & Input Output" chip or "MARIO", a backronym or acronym. The chip was later renamed "Super FX" by Nintendo.

Cartridge with Special FX Chip (1993)

"But it wasn't just a graphics chip. It was a microprocessor built to run graphics software, but it also did other things (like fast math)," explains Jez.

The Super FX chip is a 16-bit RISC processor aimed at 3D. It works as a graphics accelerator, which models and renders polygons, sprites and advanced 2D effects, to a frame buffer in RAM, which it uses to later send to the Super Nes main architecture to be displayed on the game screen. The chip has a variety of effects at its disposal, such as:

Objects that can be rotated in 3D.
Scaling and stretching sprites on 3D backgrounds.
2D parallax layers, helping Super Nes with advanced effects.
Basic texture mapping for polygonal models during rendering.

Games that make use of the special FX chip, such as Star Fox and Stunt Race FX

In the second version of the Super FX chip, access to ROM and RAM has been improved through an improved design and the fact that more pins have been added to the cartridge board. This version became known as the Super FX GSU (Graphics Support Unit), which unlike the first version of the Super FX chip, is capable of reaching 21 MHz. All versions of the Super FX chip are functionally compatible in terms of their instruction set. Argonaut also co-developed the 3D space shooter Star Fox together with Nintendo, aiming to demonstrate the additional polygon rendering capabilities that the chip would provide on the Super NES. Star Fox uses the chip to render hundreds of simultaneous 3D polygons. The game also uses scaled 2D bitmaps for the lasers, asteroids and other obstacles on the screen, but other objects, such as ships and robots, are rendered with 3D polygons. Super Mario World 2: Yoshi's Island uses the GSU-2-SP1 version for 2D graphical effects such as sprite scaling and stretching.

Because of high manufacturing costs and increased development time, few games were released for the Super FX compared to the rest of the Super NES library. Due to these costs, games with the special chip were priced higher.

Star Fox 2, deveria fazer uso do Chip FX 2

Super FX Chip Basic Specifications (16-bit)

Clock rate: 21MHz (with 10.5MHz divider).
Number of contacts on the board: 100 pins.
ROM: 1MB.
RAM: 32KB.

Super FX 2 chip (16 bits).

Clock rate: 21 MHz.
Number of contacts on board: 112 pins.
SRAM: 64 KB to 128 KB.

The tiny Super FX chip's capabilities of up to 21MHz are still very impressive today, despite its limitations being unacceptable by today's standards. Most notable is its incredibly choppy frame rate and low-resolution video output that translates to a black border around the screen. Still, these issues don't seriously affect the gameplay of games like Star Fox and Stunt Race FX.

The chip was used in 8 released SNES games, in Star Fox 2 (unreleased) and in several technology demos:

Starfox used the mario chip. Dirt Racer, Dirt Trax FX, Stunt Race FX, Vortex (demo only), and Powerslide (demo only) used the G S U 1 chip.

Doom, Star Fox 2, Super Mario World 2: Yoshis Island and Winter Gold used the G S U 2 chip.

The version of Star Fox 2 was never released for the Super Nintendo, but its version shows even more improved graphics for the 16-bit machine, making the most of its hardware and demonstrating the potential of the special chip in addition to the system's visual and computational capabilities.

Anyway, the Super FX chip arrived at the right time for Nintendo. In the midst of the console war, its main rival at that time, Sega, was gaining more and more space in the video game scene, such as Gênesis and Sega CD. The game that served to demonstrate the capabilities of the special chip added to the Super Nes, Star Fox, quickly became a success. Despite providing rudimentary 3D graphics, Super FX served to demonstrate what was to come. Providing much better gameplay than other graphics engines, such as FMV, polygonal 3D with texture mapping quickly proved to be the technology of the future.