On Fri, Sep 23, 2022, 21:50 Ali via cctalk <cctalk@classiccmp.org> wrote:
> I always thought the i960 was an upgrade to the i860 (sort of like i386 to > i486 upgrade). However, based on the info on wiki it seems as if the i960 > actually came first and although a RISC chip it was in no way in the same > league as the i860. Anyone can clarify or verify this? They're totally unrelated, except that they both came from Intel. The i960 was the BiiN processor, stripped (in most versions) of the tagged memory and capability architecture. The BiiN processor was an attempt to keep the "good parts" of the iAPX 432, without the huge performance penalty of the 432 as compared to "normal" processors (e.g., MC68000). So the i960 basically threw away the BiiN's vestiges of the 432, transforming it into a "normal" processor. It was successful in embedded applications, such as laser printer. I don't know the development history of the i860, but it is not similar in any way to the i960. There were some Unix workstations based on the i960, but many sources claim that it didn't meet expectations because of the exposed pipeline (making compiler development difficult), imprecise exceptions, and expensive context switching.
