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3 Emulated systems

This CHIP-8 emulator is compatible with other kinds of systems. CHIP-8 is based in the origina lspecification written for the first computers using CHIP-8 virtual machines inside, such as the COSMAC VIP. However, through the years, hobbyists interested in CHIP-8 emulation have developed emulators for other kinds of machines such as calculators or PCs, and they have extended the original specification for adding support to new features if the host hardware allowed so.

In particular, this emulator is at the moment compatible with CHIP-8 and SUPERCHIP ROMs.

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3.1 CHIP-8 platform

This is the original platform for the CHIP-8 virtual machine. It is a simple architecture that has the following hardware resources.

The CHIP-8 screen is a rasterized 64 x 32 pixels display. It is monochrome and up to 2048 pixels can be represented. Usually these pixels will be black and white, but there is no official statement on this, which means that is possible for some systems to use different colors, such as green over black.

CHIP-8 also has a 16 keys keyboard, as indicated in Using the emulator. It also has a buzzer that can play sounds on a particular and single frequency.

Talking about the interpreter, the CHIP-8 specification sets 34 instructions that can manipulate the data in memory, registers and stack, and interact with other IO devices such as sending images to the screen, reading keys from the keyboard or making the speaker buzz.

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3.2 SUPERCHIP platform

SUPERCHIP is an extension over the original CHIP-8 specification that appeared in the early 90s in order to run CHIP-8 games in some graphical calculators. Thanks to the new hardware capabilities of the machine, this specification adds the following features to CHIP-8:

There are 10 new instructions that cna be used in the programs. SUPERCHIP is still compatible with the original instruction set because these new opcodes are mapped to opcodes that would trigger on a crash on regular CHIP-8 emulators. A classic ROM can still work because the original instruction set is, of course, provided.

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3.3 MEGACHIP platform

This mode is not implemented yet in this emulator, although their features makes this platform very appealing.

MEGACHIP is a new format born after the improvement of personal computers. Old limitations have no place on regular devices we have today, and therefore we can have better multimedia capabilities for running games.

MEGACHIP adds support for the following features, that should be designed to be backwards compatible with CHIP-8 and SUPERCHIP formats:

There are 11 new instructions that are of course mapped to opcodes that neither CHIP-8 nor SUPERCHIP uses. Therefore, it is possible to run old CHIP-8 and SUPERCHIP games without side effects.

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