The Z8000 / Z80,000 / Z16C00 CPU homepage (original) (raw)
The Z8000 / Z80,000 / Z16C00 CPU homepage
Information and resources on the Zilog Z8000 , Z80,000 and Z16C00 series of processors
Goal of this site: To collect all available resources (documentation, software etc.) on the Z8000 series and some of the computer systems that were built with it
Remark (November 6, 2003): This is an initial version of the Z8000 website launched at November 1, 2003. In the coming weeks I will add several things and try to improve layout significantly (with material being transferred to appropriate subpages). In case you have material (software, documentation etc.) unkwown to us, please contact us (Jurjen Kranenborg)
Introduction
The Z8000 CPU series has been Zilog's contribution in the "Processor War" (i.e the competition between various 16-bit microprocessor designs during 1978-1985, before the Intel 80*86 family came out as the winner), and was introduced in 1979 between the 8086 CPU (Intel) and the 68000 CPU (Motorola). The series has been developed and produced by Zilog and second sources (AMD, SGS-ATES and Hitachi) from 1979 until approximately 1995 (?). The Z8000 CPUs appeared in two versions; a large memory version (Z8001) with 8 Mbyte addressing capability, and a small memory version (Z8002) with 64 Kbyte addressing capability. Since 1995, the CPU series continues to live - almost secretly - (and still is in production by Zilog) in a pin-compatible CMOS release called the Z16C00 series (with the Z16C01as the equivalent of Z8001 and the Z16C02as the equivalent of Z8002). The Z16C00 series appears to be applied entirely in non-commercial embedded applications..
A 32 bit follow-up called the Z80,000 has been designed in 1984 with very advanced features for that time (on-chip cache and on-chip paged memory management unit), as well as the Z8070 Floating Point Co-processor. Both designs never were released commercially (the Z80,000 made it to a test sampling phase, the Z8070 was dropped early in the design phase). However, the peripheral chips of the Z8000 family (notably the Z8030/Z8530 SCC) were very succesful and (together with enhanced versions) are still in production today (see Zilogs SCC page)
The Z8000 series introduced a number of attractive new features in the microprocessor world from the mini-computer and mainframe worlds:
- Regular general-purpose register file (16 16-bit registers that could be used as accumulators, address registers, index registers or stackpointers)
- Separation of Normal and System modes (also known as User and Supervisor modes) for enhancing system integrity
- Large address space (8Mb)
- First commercial Memory management facility (Z8010 Z-MMU)
- Extended Processing Architecture (EPA) allowing co-processing in an efficient parallel fashion
The Z8000 processor also had some drawbacks as compared to its close rival, the 68000 processor:
- Segmented addressing: maximum segment size of 64Kb which complicates the addressing of very large data structures
- Delayed introduction due to tecnical problems
- Limited support (very limited software base, limited hardware support)
Although initially the Z8000 got some acceptance and was widely recognised to have a very elegant and user-friendly architecture, it became quickly surpassed by the Motorola 68000 and the Intel 80286 in the commercial domain. In safe-critical environments however the processor apparently continued to play an important role.
Site Contents
On this site we try to collect all available resources on the Z8000 series (i.e. CPUs and support chips, including the Z80,000) and some of the computer systems that were built with it:
- Publications page on the Z8000 series and its applications (i.e technical notes, user manuals , newsgroups, etc.)
- Z8000 Software sub-page (containing both direct-code software as well as cross-assemblers and cross-compilers for high-level languages like ANSI-C, Pascal etc.)
- Z8000-based computer systems:
- Olivetti M20 (Desktop machine, see the following BYTE review, Dwight Elvey, Christian Groessler)
- Olivetti M30, M40, M50, M60 (Workstations, see following German link, Christian Groessler)
- Onyx Z8000 (First microprocessor-based Unix machine. ???)
- Plexus (???)
- Zilog S8000 (???)
- Steve Ciarcia's Trump Card (10Mhz Z8001 plug-in card for the IBM PC with 512 Kb RAM)
- Z16C00 CPU series information
- Z80,000 CPU information
- Z80,000 CPU Preliminary Technical Manual (September 1984)
* Thanks to Al Kossow
* Warning: VERY large PDF (80 Mb !)
- Z80,000 CPU Preliminary Technical Manual (September 1984)
- Open issues, requests for information:
- Other software available, please, please, please?
- Have the Z8003/4 virtual memory variants ever been produced?
- Has the Z8015 PMMU ever been produced?
- Documentation on the Z8031 ASCC (Is this a stripped (async serial only) version of the popular Z8030 SCC?)
- etc. etc.
- Home brewing projects
- Jurjen Kranenborg (still in progress, albeit slow)
- Historical Information (???)
- Discussion forum (???)
- ???
Jurjen Kranenborg, Dwight K. Elvey, Christian Groessler