Sega third generation may be the most blatant gap there. The SG-1000 came out on the very same day as the Famicom, and it is reckoned as a third-generation console. However, its actual hardware closely matches the ColecoVision, released less than a year before but which is firmly in the second generation. It doesn’t spread terribly far, either. Sega doesn’t make a major play for the international market until 1986, three years after the original SG-1000 release and one year after Nintendo started selling the Famicom internationally as the NES. The NES was a slightly modified Famicom—firmly 1983 tech, albeit very good 1983 tech that had been dominant in Japan for some time by this point. Sega’s offering—the “Master System”—was based on their Mark III console from 1985. Those extra two years were pretty busy ones in home computing—1985 in particular sees the release of the Amiga 1000 and the MSX2, both of which offered far more sophisticated graphics than their predecessors. (Indeed, the MSX 1 released the same year as the SG-1000 and had the same graphics chip!) The Master System manages a similar jump as the MSX 1-to-2 advance, or as the Atari 5200 did from the 2600 earlier in the decade.
https://bumbershootsoft.wordpress.com/2025/11/08/the-sega-master-system/ (mirror)
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https://bumbershootsoft.wordpress.com/2025/11/08/the-sega-master-system/ (mirror)
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