Nemesis

Nemesis accelerates the entire Falcon system by 50% therefore most software will run without modification. There are, however, some pitfalls to avoid.

In common with all system accelerators, Nemesis modifies the system clock. Since this clock supplies the 32MHz dot clock to the Videl chip this signal will be 32, 40 or 48MHz depending on the status of the Nemesis switches. Software which depends on the system clock being 32MHz, or requires a 32MHz dot clock to provide enhanced resolutions, will fail. Obviously this affects RGB users most because RGB resolutions use the 32MHz clock.

A switch has been provided on the Nemesis board to allow the 25MHz clock to be replaced with a 32MHz one. This allows the Falcon to be accelerated with an RGB monitor and still produce sensible video. For this reason it is inadvisable to change the dot clock when setting up the display using the hardware registers while running on an RGB monitor. Either retain the current dot clock or use Vsetmode to change resolution.

Avoid using instruction sequences to provide delay loops in timing critical code. Any FOR ... NEXT type construct will take 33% less time when Nemesis is running at 48MHz regardless of language. Use the MFP timers for accurate delays. This one applies to any accelerator.

That's it. Generally any software which is completely clean and doesn't set up it's display using the hardware registers will work perfectly well.

Nemesis Accelerator Photos

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Nemesis Buffer Photos

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Updates & Corrections to manual

PLEASE READ FIRST BEFORE INSTALLATION, ESPECIALLY POINTS 8.1 & 9.2

Installation tips

The stock Nemesis wires that come with the board are in the most part unsuitable for stable installation as they provide no shielding for the various wires that need to be attached to the board. It is recommended to replace the majority of the stock coloured wires with mini COAX cable and connect the shielding from the cable to the numerous 'e' points on the Nemesis board.

J1 == USE THE COAX FOR THIS J2 == USE THE COAX FOR THIS J3 == USE THE COAX FOR THIS J4 == USE THE COAX FOR THIS J5 == USE THE COAX FOR THIS J6 == USE THE COAX FOR THIS J7 == USE THE COAX FOR THIS

J8 == NO NEED FOR COAX / NEMISIS BOARD SWITCHING J9 == NO NEED FOR COAX \ NEMISIS BOARD SWITCHING

J10 == USE THE COAX FOR THIS

J11 == NO COAX NEEDED < NEMISIS BOARD SWITCHING

Wiring Diagram

External Links

• Nemesis Installation Manual
• Nemesis Software
• Nemesis Indicator v2 - 3rd party software accessory for Nemesis & Phantom
• Atari Forum - Discussion thread 1
• Atari Forum - Discussion thread 2
• Atari Forum - Discussion thread 3