long after the Intel 8086, but with superior features. It was basically a 16-bit processor, but could address up to 23 the upper 7 bits). There was also an unsegmented version, but both could be extended further with an additional MMU that Internally, the Z8000 had sixteen 16-bit registers, but register size and use were exceedingly flexible. The Z-8000 registers could be used as sixteen 8-bit registers (only the first half were used like this), sixteen 16-bit registers, eight 32-bit registers, or four 64-bit registers, and included 32-bit multiply and divide. They were all general purpose with register 14 holding the stack segment (both accessed as one 32-bit register for painless address calculations). and one for user programs. The user mode prevented the user from messing about with interrupt handling and other potentially dangerous stuff. Finally, like the Zilog Z80, the Z8000 featured automatic but the features generally made up for that. Initial bugsalso hindered its acceptance (partly because it did not use microcode). There was a radiation resistant military version. (1997-12-16)
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