<
processor> A
microprocessor from
Zilog introduced not long after the
Intel 8086, but with superior features. It was basically a 16-bit
processor, but could address up to 23 bits in some versions by using
segment registers (to supply the upper 7 bits). There was also an unsegmented version, but both could be extended further with an additional
MMU that used 64
segment registers. 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 registers - the
stack pointer was typically register 15, with register 14 holding the stack segment (both accessed as one 32-bit register for painless address calculations). The Z8000 featured two modes, one for the
operating system 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
DRAM refresh circuitry. Unfortunately it was somewhat slow, but the features generally made up for that. Initial
bugs also hindered its acceptance (partly because it did not use
microcode). There was a radiation resistant military version. There was a later 32-bit,
pipelined version, the {Zilog Z80000}. (1997-12-16)
In addition suitable contents:
[ 2 ] [ 64-bit ] [ 8086 ] [ = ] [ accept ] [ ad ] [ address ] [ af ] [ ai ] [ al ] [ AM ] [ am ] [ an ] [ ar ] [ arc ] [ as ] [ at ] [ au ] [ b ] [ ba ] [ be ] [ bi ] [ bit ] [ bo ] [ bot ] [ by ] [ ca ] [ cc ] [ ch ] [ ci ] [ circuit ] [ ck ] [ cl ] [ co ] [ code ] [ cr ] [ cu ] [ D ] [ dd ] [ de ] [ ding ] [ DRAM ] [ DRAM refresh ] [ du ] [ ec ] [ ed ] [ ee ] [ eg ] [ er ] [ era ] [ es ] [ event ] [ extend ] [ feature ] [ fi ] [ file ] [ fo ] [ for ] [ fr ] [ ge ] [ gen ] [ gh ] [ gi ] [ gl ] [ gm ] [ gr ] [ gs ] [ h ] [ hat ] [ hr ] [ ht ] [ id ] [ il ] [ in ] [ inc ] [ include ] [ int ] [ interrupt ] [ io ] [ ir ] [ is ] [ it ] [ ke ] [ la ] [ lc ] [ ld ] [ Lex ] [ li ] [ like this ] [ line ] [ ls ] [ lt ] [ lu ] [ ly ] [ M ] [ ma ] [ micro ] [ microcode ] [ microprocessor ] [ mil ] [ MMU ] [ mo ] [ mod ] [ mode ] [ module ] [ ms ] [ mu ] [ na ] [ nc ] [ ne ] [ nf ] [ ng ] [ ni ] [ nl ] [ no ] [ ns ] [ om ] [ op ] [ operating system ] [ pa ] [ pe ] [ ph ] [ pipe ] [ pipeline ] [ pipelined ] [ pl ] [ ply ] [ point ] [ pointer ] [ pr ] [ process ] [ processor ] [ program ] [ pt ] [ query ] [ RAM ] [ rc ] [ re ] [ refresh ] [ register ] [ ro ] [ ru ] [ se ] [ segment ] [ sh ] [ si ] [ sl ] [ so ] [ st ] [ stack ] [ stack pointer ] [ su ] [ sy ] [ system ] [ T ] [ tar ] [ tee ] [ th ] [ to ] [ tr ] [ tw ] [ ug ] [ up ] [ us ] [ user ] [ ve ] [ version ] [ vi ] [ Z ] [ Z8 ] [ Z80 ] [ Z8000 ] [ Zilog ] [ Zilog Z8 ] [ Zilog Z80000 ]