Mega II Chip on the IIGS

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Mega II Chip on the IIGS

Hiya folks,


So, as I understand it, the IIGS has a single chip which is essentially emulating all of the functions of the original Apple II. So, since the computer would boot by default to the BASIC prompt, does that mean that the computer was designed to boot directly into the Mega II chip in "emulation mode" and not use any of the higher 16-bit level stuff unless necessary/prompted?

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The Mega II chip combines the

The Mega II chip combines the Apple IIe's MMU, IOU, and most of the TTLs on an Apple IIe board. It is not a complete computer on its own, and more or less all of the chips in the Apple IIgs are in use whether it runs in 8 or 16 bit mode. Specifically, the FPI/CYA chip is required to communicate with the CPU, and the VGC chips is required to produce video output, as well as the ROM and RAM chips.

The IIgs does not boot by default to Basic. It expects to boot from a disk (DOS 3.3, ProDOS8, ProDOS16, or GS/OS) and displays "check startup device" if one is not found. You can enter AppleSoft Basic by pressing the reset key.

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