View source for HP FOCUS

{{Short description|Hewlett-Packard microprocessor}}
[[File:HP-HP9000-Focus-CPU-Board-5061-6803 03.jpg|thumb|right|alt=Hewlett-Packard HP9000 Series 500 FOCUS-CPU; NMOS-III Finstrate CPU - 32Bit - 18 MHz - consist of five chips on one board: CPU, IO-Processor (IOP), Memory Controller (MMU), 16kx8 DRAM, Clock Chip - 450000 FETs - HP Part Number: 5061-6803 - front side look modified with transparent chip covers|HP FOCUS processor and support chips on "finstrate" board]]
The [[Hewlett-Packard]] '''FOCUS''' [[microprocessor]], launched in 1982, was the first commercial, single chip, fully [[32-bit]] microprocessor available on the market. At this time, all [[32-bit]] competitors ([[Digital Equipment Corporation|DEC]], [[IBM]], [[Prime Computer]], etc.) used multi-chip [[Bit slicing|bit-slice]]-CPU designs, while single-chip designs like the [[Motorola 68000]] were a mix of 32 and 16-bit.
Introduced in the Hewlett-Packard [[HP 9000#Series 500|HP 9000 Series 500]] workstations and servers (originally launched as the HP 9020 and also, unofficially, called HP 9000 Series 600), the single-chip CPU was used alongside the I/O Processor (IOP), Memory Controller (MMU), Clock, and a number of 128-kilobit dynamic [[Random-access memory|RAM]] devices<ref name="wheeler198308">{{ cite journal | url=https://archive.org/details/Hewlett-Packard_Journal_Vol._34_No._8_1983-08_Hewlett-Packard/page/n19/mode/1up | title=128K-Bit NMOS Dynamic RAM with Redundancy | last1=Wheeler | first1=John K. | last2=Spencer | first2=John R. | last3=Beucler | first3=Dale R. | last4=Kohlhardt | first4=Charlie G. | journal=Hewlett-Packard Journal | date=August 1983 | accessdate=6 October 2020 | volume=34 | issue=8 | pages=20–24 }}</ref> as the basis of the HP 9000 system architecture.<ref name="beyers198308">{{ cite journal | url=https://archive.org/details/Hewlett-Packard_Journal_Vol._34_No._8_1983-08_Hewlett-Packard/page/n2/mode/1up | title=VLSI Technology Packs 32-Bit Computer System into a Small Package | journal=Hewlett-Packard Journal | last1=Beyers | first1=Joseph W. | last2=Zeller | first2=Eugene R. | last3=Seccombe | first3=S. Dana | date=August 1983 | accessdate=6 October 2020 | volume=34 | issue=8 | pages=3–6 }}</ref> It was a 32-bit implementation of the [[16-bit]] [[HP 3000]] computer's [[stack architecture]],<ref name="burkhart198308">{{ cite journal | url=https://archive.org/details/Hewlett-Packard_Journal_Vol._34_No._8_1983-08_Hewlett-Packard/page/n6/mode/1up | last1=Burkhart | first1=Kevin P. | last2=Forsyth | first2=Mark A. | last3=Hammer | first3=Mark E. | last4=Tanksalvala | first4=Darius F. | title=An 18-MHz, 32-Bit VLSI Microprocessor | journal=Hewlett-Packard Journal | date=August 1983 | accessdate=6 October 2020 | volume=34 | issue=8 | pages=7–8, 10, 11 }}</ref> with over 220 instructions (some 32 bits wide, some 16 bits wide), a segmented memory model, and no general purpose programmer-visible [[Processor register|registers]].<ref name="fiasconaro198308">{{ cite journal | url=https://archive.org/details/Hewlett-Packard_Journal_Vol._34_No._8_1983-08_Hewlett-Packard/page/n8/mode/1up | title=Instruction Set for a Single-Chip 32-Bit Processor | last1=Fiasconaro | first1=James G. | journal=Hewlett-Packard Journal | date=August 1983 | accessdate=6 October 2020 | volume=34 | issue=8 | pages=9–10 }}</ref> The design of the FOCUS CPU was richly inspired by the custom [[silicon on sapphire]] (SOS) chip design HP used in their HP 3000 series machines.
Because of the high density of HP's [[NMOS logic|NMOS-III]] IC process,<ref name="mikkelson198308">{{ cite journal | url=https://archive.org/details/Hewlett-Packard_Journal_Vol._34_No._8_1983-08_Hewlett-Packard/page/n26/mode/1up | title=NMOS-III Process Technology | last1=Mikkelson | first1=James M. | last2=Fei | first2=Fung-Sun | last3=Malhotra | first3=Arun K. | last4=Seccombe | first4=S. Dana | journal=Hewlett-Packard Journal | date=August 1983 | accessdate=6 October 2020 | volume=34 | issue=8 | pages=27–30 }}</ref> heat dissipation was a problem. Therefore, the chips were mounted on special [[printed circuit board]]s, with a ~1&nbsp;mm copper sheet at its core, called [[insulated metal substrate|"finstrates"]].<ref name="malhotra198308">{{ cite journal | url=https://archive.org/details/Hewlett-Packard_Journal_Vol._34_No._8_1983-08_Hewlett-Packard/page/n23/mode/1up | title=Finstrate: A New Concept in VLSI Packaging | last1=Malhotra | first1=Arun K. | last2=Leinbach | first2=Glen E. | last3=Straw | first3=Jeffery J. | last4=Wagner | first4=Guy R. | journal=Hewlett-Packard Journal | date=August 1983 | accessdate=6 October 2020 | volume=34 | issue=8 | pages=24–26 }}</ref><ref name="weissmann">
{{cite web | title=OpenPA: HP 9000/500 FOCUS | work=Paul Weissmann | url=http://www.openpa.net/systems/hp-9000_520.html | accessdate=February 25, 2005 }}
</ref>
The Focus CPU is [[microcode]]d with a 9,216 by 38-bit microcode [[control store]]. Internal data paths and registers are all 32-bit wide. The Focus CPU has a [[transistor count]] of 450,000 FETs.<ref name="burkhart198308" /><ref name="weissmann" />
==References==
{{reflist}}
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* {{cite web | title=HP Computer Museum: Technical Desktops: Series 500 | url=http://hpmuseum.net/exhibit.php?class=1&cat=12 }} See {{cite web | title=Product Documentation | url=http://hpmuseum.net/exhibit.php?catdoc=12 }} for HP Journal articles.
*{{cite journal |journal=HP Journal |volume=34 |issue=8 |date=August 1983 |title=HP 9000 |url=http://hparchive.com/Journals/HPJ-1983-08.pdf }}
*{{cite journal |title=A 32-bit VLSI CPU chip |first1=J.W. |last1=Beyers |first2=L.J. |last2=Dohse |first3=J.P. |last3=Fucetola |first4=R.L. |last4=Kochis |first5=C.G. |last5=Lob |first6=G.L. |last6=Taylor |first7=E.R. |last7=Zeller |journal=IEEE Journal of Solid-State Circuits |volume=16 |issue=5 |date=October 1981 |pages=537–542 |doi=10.1109/JSSC.1981.1051634|bibcode=1981IJSSC..16..537B |s2cid=21460202 }}
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{{DEFAULTSORT:Hp Focus}}
[[Category:HP microprocessors|FOCUS]]
[[Category:Stack machines]]
[[Category:32-bit microprocessors]]
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