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A little background on the Atari 2600 will help to clarify what the Cuttle Cart does. The design of the Atari 2600 limits it to accessing at most 4K of cartridge ROM, and does not provide any support for the use of RAM inside a cartridge. This became a limiting factor in what types of games could be produced for the 2600, so techniques were created which would allow designers to use more than 4K of ROM in their games and to include additional amounts of RAM as well. These techniques are known as bankswitching (technically this refers to the way of increasing ROM space, not to adding extra RAM.) Bankswitching used special hardware inside the cartridge itself that would swap one area of ROM for another when certain key addresses were accessed. This allows access to more than 4K of ROM by accessing different 4K blocks at different times. Similar additional hardware was also used for the inclusion of additional RAM inside the cartridge.
Various manufacturers used different techniques to acheive this bankswitching, each technique requiring its own set of custom hardware inside the cartridge. The original Starpath Supercharger used its own method of bankswitching to allow games to be up to 6K in size. In addition, it provided a means to access the entire 6K as RAM, not just ROM. Larger games could be created using multiple loads off tape into the Supercharger for different parts of the game.
Recently, the Supercharger has gained popularity because Bob Colbert determined how to use the Supercharger to play standard 2K and 4K games, although this requires a hardware modification to the Supercharger to play many of the existing games. However, the Supercharger cannot be used to play any games larger than 4K except those that were specifically designed to work with the Supercharger.
And thus enters the Cuttle Cart. The Cuttle Cart uses the same audio interface as the original Supercharger, but contains 64K of RAM instead of the 6K of the original Supercharger. In addition, the Cuttle Cart contains the hardware to implement almost all of the known Atari 2600 bankswitching and extra RAM techniques, and it can do all of this using control codes in the downloaded game rather than requiring a hardware modification or switch.
This allows the Cuttle Cart to be used to play almost any existing Atari 2600 game, or to develop new games using any existing bankswitching technique, and distribute those games on CD or as .bin files for use by other people on their Atari 2600. And of course it does this while maintaining full backwards compatability with an *unmodified* Supercharger. (See below for details concerning modified Superchargers.)
To use the Cuttle Cart, one requires an audio source to load the games while the Cuttle Cart is plugged into the Atari 2600. This can be either a CD or Tape with the games in the proper format, or a computer with the capability of playing .wav files. A program for converting games to the necessary audio format will be supplied with the Cuttle Cart. I will not provided CDs or Tapes of games however. The audio connector on the Cuttle Cart is a standard 1/8th inch mono plug. (Typical of the connector for portable headphones, only in mono rather than stereo. It can be plugged directly into a stereo source.) Please note that there is no persistent memory on the Cuttle Cart. Once you turn off the 2600, the game must be reloaded.
The Cuttle Cart can be considered to be an extension to the original Starpath Supercharger, and in fact the audio loading format of the Supercharger has been licensed for use in the Cuttle Cart from Bridgestone Multimedia, the company that owns the rights to the Supercharger and its library of games.
There are plans on the Internet to modify a Starpath Supercharger to make it compatible with all of the 2K and 4K Atari 2600 games (many of which will not work in an unmodified Supercharger.) This modification involves installing a logic chip and a switch into the Supercharger. The switch is used to tell the Supercharger whether it should work as originally designed (to play the Supercharger games themselves) or in 2K/4K mode to play standard Atari 2600 games.
The Cuttle Cart is designed such that this switch is not required. Instead of a hardware switch to select the mode the Cuttle Cart operates in, the mode is selected by information downloaded at the same time the game is loaded. In fact, this is how the Cuttle Cart selects any of the bankswitching modes it supports, and 2K and 4K are just two of the particular modes available. This information is sent in a portion of the header that is not used by the original Supercharger, and thus when you load original Supercharger games, the Cuttle Cart knows to operate in orignal Supercharger mode because there is no command to switch to another mode.
Unfortunately, this creates a small problem with audio CD game collections which were created to load games into a *modified* Supercharger. The 2K and 4K games on these collections will NOT contain the extra information to tell the Cuttle Cart to switch to 2K or 4K mode. (Remember, this was accomplished with a hardware switch that doesn't exist on the Cuttle Cart.) Without this extra information, the Cuttle Cart will operate in Supercharger mode, and thus the games which require 2K and 4K mode will not work (just like they wouldn't work on an unmodified Supercharger.)
So what does this mean to you? If you don't own a modified Supercharger, or a collection of games already in audio format for use on the modified Supercharger, this means nothing to you. All of the 2K and 4K games will work fine on the Cuttle Cart and will be properly formatted by the software included with the Cuttle Cart. If you do own a collection of games formatted for the modified Supercharger, such as Worship the Woodgrain, then you'll need to replace those CD's with ones created to work with the Cuttle Cart, or to tie it into the above description, with games that contain the extra data to tell the Cuttle Cart to operate in 2K or 4K mode.
The core of the Cuttle Cart is a Xilinx CPLD (Complex Programmable Logic Device), programmed to support all the bankswitching modes. Also present are the ROM containing the startup code and the loading routines, 64K of SRAM, and some addititional support electronics to generate time delays and convert the audio signal to a digital signal.