Hardware chronology

The Alpha68k is an arcade board type from 1986 designed by Alpha Denshi which is believed to be the hardware on which the NeoGeo was built.

The Alpha68k is interesting in that it mainly uses classic logic chips instead of ASICs, which reveals lots of the NeoGeo's GPU design.

It can't do sprite shrinking and has inferior sound.

Similarities

• 68k/Z80 pair.
• Same resolution.
• Same dual line buffer system.
• Fix layer.
• Uses an early PRO-CT0 chip, same sprite graphics format.
• Line buffers are cleared to all-ones by pull-up resistors, the NeoGeo also does this (see backdrop color in palettes).