Commodore 900
Template:Short description Template:Infobox information appliance The Commodore 900 (also known as the C900, Z-8000, and Z-Machine)<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="hughes1985">Template:Cite book</ref> was a prototype microcomputer originally intended for business computing and, later, as an affordable UNIX workstation.<ref name="commodoreinfo_c900">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>Template:Cite book</ref><ref>Template:Cite book</ref> It was to replace the aging PET/CBM families of personal computers that had found success in Europe as business machines. The project was initiated in 1983 by Commodore systems engineers Frank W. Hughes, Robert Russell, and Shiraz Shivji.<ref>Bagnall, Brian (2006). On the Edge: The Spectacular Rise and Fall of Commodore, Variant Press. Page 434. Template:ISBN</ref>
In early 1983, Commodore announced an agreement with Zilog to adopt the Z8000 family of processors for its next generation of computers, conferring rights to Commodore to manufacture these processors and for Zilog to manufacture various Commodore-designed integrated circuit products. Zilog was to manufacture components for Commodore's computers, allowing Commodore to expand its own semiconductor operation.<ref name="computerworld19830124_zilog">Template:Cite magazine</ref> Commodore had reportedly been developing its own 16-bit microprocessor, abandoning this effort to adopt the Z8000.<ref name="computerselectronics198403_6502">Template:Cite magazine</ref>
DesignEdit
The C900 was a 16-bit computer based on the segmented version of the Zilog Z8000 CPU.<ref name="zimmers_c900">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Initial announcements indicated the use of a 10 MHz Z8001 processor,<ref name="microcomputers-sep-oct-85" /> but earlier technical documentation suggested the use of a 6 MHz part and detailed the option of a Z8070 arithmetic processing unit (APU) running at 24 MHz.<ref name="hughes1985"/> The specification as announced in 1984 featured 256 KB of RAM and a 10 MB hard drive,<ref name="commodoreuser198405_hanover">Template:Cite magazine</ref> but subsequently settled on 512 KB of RAM and a 20 MB hard drive as the minimum configuration, with 40 MB and 67 MB hard drives offered as options.<ref name="commodoreinfo_c900"/> A minimum configuration system had been expected to provide only 128 KB of RAM and a 320 KB floppy drive, selling for under $1,000.<ref name="computerselectronics198403_rumors">Template:Cite magazine</ref>
Two versions of the machine were developed: a workstation with Template:Nowrap pixel graphics and a multi-user system featuring a text-only display intended to act as a server for a number of connected character-based terminals.<ref name="zimmers_c900" /><ref name="commodoreinfo_c900" /> For the text-only configuration and for lower-resolution graphical output, the system employed the MOS Technology 8563 video controller,<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> this supporting an Template:Nowrap colour textual display or a Template:Nowrap colour graphical display.<ref name="hughes1985"/> The high-resolution display option employed 128 KB of dedicated video memory and featured hardware support for blitting operations, this being employed by a graphical environment featuring "multiple overlapping windows".<ref name="commodoreinfo_c900" />
The C900 ran Coherent, a UNIX-like operating system,<ref name="commodoreinfo_c900" /> claimed in publicity as being "fully compatible with AT&T's Unix System V, version 5.2",<ref name="microcomputers-sep-oct-85"/><ref name="computerworld19850506_commodore"/> although the Coherent system was generally regarded as merely providing a level of compatibility with Version 7 Unix.<ref name="byte198511_rochkind">Template:Cite magazine</ref> Some observers found the choice of an earlier form of Unix "surprising" given the availability of more recent versions and of Zilog's commitment among other manufacturers to promote System V as the industry standard for Unix.<ref name="commodoreuser198405_hanover"/> Onyx Systems, a pioneer of Z8000-based systems running Unix, had previously delivered ports of Version 7 Unix<ref name="onyx_c8002">Template:Cite book</ref> and Unix System III for their computers.<ref name="onyx_c5002a">Template:Cite book</ref>
Manufacturing of the system was to commence in 1985 at Commodore International's West Germany plant, with availability in the United States announced for the third quarter of the same year, and with pricing starting from approximately $2,700.<ref name="computerworld19850506_commodore">Template:Cite magazine</ref> The machine was publicly demonstrated for the first time outside the US at the 1985 Hanover Fair, with interest in the product described as "overwhelming".<ref name="commodorenews1985">Template:Cite magazine</ref> Ultimately, only fifty prototypes were made and sold as development systems before the project was cancelled.
The C900's case is similar to the Amiga 2000's but slightly larger.
See alsoEdit
ReferencesEdit
External linksEdit
- C900 page at 'The Secret Weapons of Commodore' website – By Cameron Kaiser and The Commodore Knowledge Base
- This is Z page – By Bo Zimmerman
- The Commodore C900 – color photos of a prototype unit
- Commodore C900 product announcement
- A running CBM900 has survived at datamuseum.dk and several of the ROMs have been reverse-engineered.
- Commodore Microcomputer magazine coverage of the 900's announcement
- Commodore 900: The Unix-like workstation/server that was eclipsed by Amiga
