Apple II accelerators

Apple II accelerators are computer hardware devices which enable an Apple II computer to operate faster than their intended clock rate.

Number Nine Apple Booster (1982) was one of the first accelerators for the Apple II series of computers. This card is the original version of Saturn's Accelerator II (thus the Accelerator II PCB shares both Saturn Systems' and NNCC's logos.) At $598, the Saturn was much cheaper than the NNCC, but little information about the board is available today.

Microcomputer Technologies (M-c-T) SpeedDemon card was the one of early Apple II accelerator which used the newer 65c02 microprocessor, and the first to implement caching technology. This allowed the card to use small amounts of memory, making the card less expensive to produce and eliminated the need to waste clock cycles in order to refresh the dynamic RAM that other cards used. Other accelerators which did not use caching operated at 3.56 MHz most of the time but had to slow down to 1 MHz for this refresh cycle. For peripheral cards that required 1 MHz "slow" operations, the Speed Demon always slowed access to slot #6 to 1 MHz, while an on-card jumper controlled the slot #4 and #5 slowdown. The SpeedDemon originally retailed for $295.

Saturn System's Accelerator II was the original accelerator for the Apple II series of computers. The card accelerated the Apple II and the Apple II Plus using a faster MOS 6502 microprocessor and on-board high speed RAM. When the accelerator card was activated, software would execute within the CPU and memory on the card, not utilizing those components on the motherboard. The card used a series of 8 DIP switches to configure slot access speeds as well as the speed of the card. Since the Accelerator was released before Apple Computer's introduction of the Apple IIe. The card would run in an Apple IIe, however software which required a 65C02 microprocessor or used auxiliary memory would not function properly; a problem which was solved with the Accelerator //e, a complete redesign. Saturn Systems changed their name during the early 1980s to Titan Technologies due to trademark complications.

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