Editing Motorola 68008

{{Short description|Microprocessor}}
{{More citations needed|date=June 2021}}
[[Image:KL_Motorola_MC68008.jpg|thumb|Motorola MC68008]]
[[Image:Sincalir-QL-68008-Processor.jpg|thumb|68008 in a [[Sinclair QL]] motherboard]]

[[File:STEbus 68008 CPU on 100x160mm Eurocard.jpg|thumb|STEbus 68008 processor]]

The '''Motorola 68008''' is an 8/32-bit [[microprocessor]] introduced by [[Motorola]] in 1982. It is a version of 1979's [[Motorola 68000]] with an [[8-bit]] external [[computer bus|data bus]], as well as a smaller [[address bus]].<ref name=68kusermanual>{{cite web
| url     = https://www.nxp.com/docs/en/reference-manual/MC68000UM.pdf 
| title   = M68000 8-/16-/32-Bit Microprocessors User's Manual, Ninth Edition
| website = [[NXP Semiconductors]]
| author  = [[Motorola]]
| year    = 1993
}}</ref> The 68008 was available with 20 or 22 address lines (in a 48-pin or 52-pin package, respectively) which allowed 1 MB or 4 MB address space versus the 16 MB addressable on the 68000. The 68008 was designed to work with lower cost and simpler 8-bit memory systems. Because of its smaller data bus, it was roughly half as fast as a 68000 of the same clock speed.<ref name=68kusermanual /> It was still faster than competing 8-bit microprocessors,{{dubious|date=September 2021|reason=Performance claims come from vendor}} because internally the 68008 behaves identically to the 68000 and has the same [[microarchitecture]].{{sfn|Motorola|1993|page=1-2}}

Motorola ended production of the 68008 in 1996.<ref>[http://groups.google.com/group/comp.sys.m68k/browse_frm/thread/ab9a8520ee794d85/cedb5e4f449f346c comp.sys.m68k Usenet posting], May 16, 1995; also see other posts in thread.  The end-of-life announcement was in late 1994; according to standard Motorola end-of-life practice, final orders would have been in 1995, with final shipments in 1996.</ref>

==Details==
The 68008 is an [[HMOS]] chip with about {{nowrap|70,000 transistors;}} with a speed grade of {{nowrap|8 and 10 MHz}}. There are two versions of the chip. The original is in a 48-pin [[dual in-line package]] with a 20-bit address bus, allowing it to use up to 1 [[megabyte]] of memory. A later version is in a 52-pin [[plastic leaded chip carrier]]; this version has a 22-bit address bus and can support {{nowrap|4 megabytes}} of RAM.{{sfn|Motorola|1993|page=3-4}}

==Usages==
The [[Sinclair QL]] [[microcomputer]] and [[Luxor_AB|Luxor]] [[ABC 1600]] use the 68008 as their main processor.

== References ==
{{Reflist}}

== External links ==
* [http://wandel.ca/homepage/mc68008/index.html A small 68008 design]
* [http://www.ist-schlau.de Kiwi - an 68k Homebrew Computer]

{{Motorola processors}}

[[Category:68k microprocessors]]