--- title: Olivetti M20 categories: - Computers types: - Professional Computer origins: - Italy years: - '1982' cpus: - Zilog Z8001 params: name: M20 company: /companies/olivetti company_name: Olivetti specs: - label: NAME value: M20 - label: MANUFACTURER value: Olivetti - label: TYPE value: Professional Computer - label: ORIGIN value: Italy - label: YEAR value: March 1982 - label: BUILT IN LANGUAGE value: None - label: KEYBOARD value: Full-Stroke 120 keys with numeric keypad - label: CPU value: Zilog Z8001 - label: SPEED value: 4 Mhz - label: CO-PROCESSOR value: None - label: RAM value: 128 KB expandable to 512 KB - label: ROM value: 12 KB (BIOS) - label: TEXT MODES value: 80 columns x 25 lines - label: GRAPHIC MODES value: 512 x 256 pixels in 4 colours maximum - label: COLORS value: 4 or 8 with RAM extension board - label: SOUND value: Beeper - label: SIZE / WEIGHT value: '42.5(W) x 51.4(D) x 15(H) cm. Weight: 10.5 Kg.' - label: I/O PORTS value: 1 x RS-232 port, 1 x RS-1232C enhanced serial port, 1 x custom monitor connector, 1 x Parallel printer port - label: BUILT IN MEDIA value: |- 2 x 160, 320 or 640 KB 5.25'' F.D. drives\ or 1 x F.D. drive + 1 x 11.25 MB Hard disk - label: OS value: PCOS, CP/M8000, MS-DOS (with the APB 8086 card) - label: POWER SUPPLY value: Built-in power supply - label: PERIPHERALS value: 128 KB memory card, Intel 8086 microprocessor card, IEEE-488 card - label: PRICE value: $5400 (2 x F.D. version) tabs: - photos - adverts - links - docs photos: - title: NICE ITALIAN DESIGN subtitle: '' text: '' image: null - title: M-20 KEYBOARD subtitle: '' text: Keyboard and built-in F.D. drives close-up image: null - title: INSIDE M-20 subtitle: '' text: |- The M-20 was a well designed system. Each part of the computer can be removed and put back without any tool. **(1)** 2 x Expansion board connectors. The optional 8086 board takes place here.\ **(2)** 3 x Expansion memory boards. Up to 3 x 128 KB boards can be inserted.\ **(3)** 128 KB on-board RAM memory chips (16 x 4164)\ **(4)** Zilog Z-8001 microprocessor\ **(5)** BIOS ROM chips\ **(6)** Power supply unit image: null - title: UNCOVERED SYSTEM subtitle: '' text: '' image: null adverts: - title: 'U.S. AD #1 (1982)' subtitle: '' text: |- Advert said: We know your question: How could Olivetti have developped a better personal computer than the other giants?\ The answer is in a word: Experience. Olivetti introduced the world's first desktop computer in 1965. Since then, we've continued to market a variety of minicomputers and microcomputers to a wide range of users... image: null - title: 'U.S. AD #2 (1983)' subtitle: '' text: Despite the M20 was neither software nor hardware compatible with any other computer, Olivetti had to prove that it had more computing power at a smaller pice than any competitor. image: null - title: U.S. AD. JUNE 1983 subtitle: '' text: '' image: null - title: GERMAN ADVERT subtitle: '' text: '' image: null - title: THE FIRST M20 VERSION subtitle: '' text: |- This Olivetti ancestor, also called M20, was born in 1920...\ To note the superb design all the young italian secretaries were in love of! Thanks to Karl-Heinz - www.sharpmz.org image: null links: - title: Olivetti M20 site url: http://www.z80ne.com/m20/index.php?argument=home.inc text: Very complete, detailed and useful site for any M20 owner. docs: - title: USER MANUAL (GERMAN) url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**USER MANUAL (GERMAN)**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Chris Groessler\  type of document : PDF\  size : 3.2 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: INSTALLATION AND USE GUIDE (ITALIAN) url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**INSTALLATION AND USE GUIDE (ITALIAN)**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Tix (1000bit.net)\  type of document : PDF\  size : 49 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: HARDWARE MANUAL url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**HARDWARE MANUAL**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Chris Groessler\  type of document : PDF\  size : 5.3 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: HARDWARE MANUAL - PART 2 url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**HARDWARE MANUAL - PART 2**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Chris Groessler\  type of document : Unknown\  size : 5.8 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: OLIVETTI M20 QUICK REFERENCE GUIDE url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**OLIVETTI M20 QUICK REFERENCE GUIDE**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Chris Groessler\  type of document : PDF\  size : 4.7 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: PC-OS (ITALIAN) url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**PC-OS (ITALIAN)**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by prof.ing. Dino Molli\  type of document : PDF\  size : 7.3 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: ASSEMBLER MANUAL AND RELATIONSHIPS WITH PC-OS url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**ASSEMBLER MANUAL AND RELATIONSHIPS WITH PC-OS**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Chris Groessler\  type of document : PDF\  size : 19.1 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: M20 MICROSOFT BASIC (ITALIAN) url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**M20 MICROSOFT BASIC (ITALIAN)**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by prof.ing. Dino Molli\  type of document : PDF\  size : 11.6 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: M20 ISAM MANUAL (ITALIAN) url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**M20 ISAM MANUAL (ITALIAN)**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Chris Groessler\  type of document : PDF\  size : 10.1 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: M20 ISAM MANUAL (ITALIAN) url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**M20 ISAM MANUAL (ITALIAN)**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by prof.ing. Dino Molli\  type of document : PDF\  size : 3.4 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: M20 OLISORT MANUAL (ENGLISH) url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**M20 OLISORT MANUAL (ENGLISH)**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Chris Groessler\  type of document : PDF\  size : 24 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: M20 OLISORT MANUAL (ITALIAN) url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**M20 OLISORT MANUAL (ITALIAN)**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by prof.ing. Dino Molli\  type of document : PDF\  size : 14.7 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: M20 OLIWORD MANUAL (ITALIAN) url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**M20 OLIWORD MANUAL (ITALIAN)**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Dwight Elvey and to Chris Groessler\  type of document : PDF\  size : 4.7 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: I/O WITH EXTERNAL PERIPHERALS MANUAL url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**I/O WITH EXTERNAL PERIPHERALS MANUAL**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Chris Groessler\  type of document : PDF\  size : 14.6 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) - title: ZILOG Z8000 PROGRAMMING GUIDE url: http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc cover: null text: |- [**ZILOG Z8000 PROGRAMMING GUIDE**](http://www.z80ne.com/m20/index.php?argument=sections/manuals/manuals.inc)written by Olivetti  compiled/archived by Jurjen Kranenborg\  type of document : PDF\  size : 4.7 MB\  source : [Olivetti M20 site](http://88.164.48.108/index.php) comments: - author: PETER WALSH (USA) date: Thursday 19th May 2022 text: Does anyone know what a chord keyboard is? Peter Walsh - author: Oliver (Germany) date: Wednesday 30th December 2020 text: Hi, I have a Memory Expansion for this machine für sell or Trade Cheers Oliver - author: BoredBot date: Tuesday 29th November 2016 text: 'Olivetti M20: A bit of a cheese machine, easily blown away by an old standard XT. No style.' - author: Steve (Tennessee) date: Monday 25th July 2016 text: |- Hi, I''m still looking for an M-20 to buy. If I can''t find one I do have many old books\ and some old software on floppy for an M-20\ stecla1@gmail.com - author: Edward Williams (United States) date: Tuesday 10th March 2015 text: |- Looking to buy am Olivetti M20 I had one years ago i lost in a fire i have my original source code,\ Thanks\ Edward1469@mac.com - author: scott-m (USA) date: Thursday 11th December 2014 text: |- Hmmm. . .\ The equals sign in the youtube.com URL got changed to a dollars sign. Odd. Just search youtube.com for "Olivetti M20 artillery command game", and you will find it.\ -Scott M - author: scott-m (USA) date: Thursday 11th December 2014 text: |- Dec 11, 2014 - My Dad shipped the Olivetti M20. The new owner said: I was able to unbox and set up the computer, and was even able to run some of my old BASIC programs and games I wrote 30 years ago. I made a youtube of one game I made, "Artillery Command". It''s a little blurry because my camera had a hard time focusing on the screen, but if you want to see what a 15 year old me did 30 years ago, here it is: https://www.youtube.com/watch?v$xotIGWC02MU Glad the M20 found a new home.\ -Scott M - author: scott-m (USA) date: Saturday 15th November 2014 text: 'Nov 15, 2014 - My Dad has a Olivetti M20 in like-new condition with engineering software. He is the original owner and will sell it for just the cost of shipping. Tried to register on old-computers.com, but never got an activation email. old-computers.com generated this error message: The message could not be sent to the SMTP server. The transport error code was 0x80040217. I think outgoing email from this website is not working. Anyway, for that reason I am simply going to put my contact information in this message. Remove all letters ''''x'''' from the following email address: xxsxcoxtx.xmx.2x2x @ xaxtxsxgxaxtxex.xcxoxmxx If you are reading this after February 2015, the computer is most likely already gone. Thanks! -Scott M' - author: steve (USA) date: Saturday 9th August 2014 text: |- I''m still looking for an M20 to buy,\ But if not I have floppies and books for the M20 if someone wants to buy them. - author: Steve (USA) date: Sunday 1st December 2013 text: I''m still interested in buying an M-20 or motherboard for one. I have box monitor and power supply and keyboard etc. but Dominique I''m still interested if you have one to sell. - author: Vincenzo (Italy) date: Thursday 1st August 2013 text: |- hello, I own 28 or 29 Olivetti M20s of different models. I''m searching the COLOR MONITOR and the GPIB board (GO220). It is missing to my collection. Anybody can sell it to me? Regards, Vincenzo. - author: Steve (USA) date: Saturday 4th August 2012 text: Dominique, I''m interested in your m20 - author: Graham Reid (UK) date: Tuesday 14th February 2012 text: |- Hi Dominique, I''ve been transcribing the M20 schematics into Eagle so that I can create an equivalent. However, a real machine would be invaluable to correct the mistakes on the diagrams. How much would you want for your M20?\ (If anyone has a dead motherboard, I''m interested!)\ Regards, Graham - author: Dominique Carton date: Monday 2nd January 2012 text: I have an Olivetti M20 computer with two floppy drives and programs and documentation, anything I needed to have when I used it. Would consider selling it. - author: Dominique Carton date: Monday 2nd January 2012 text: I have an Olivetti M20 computer with two floppy drives and programs and documentation, anything I needed to have when I used it. Would consider selling it. - author: Dominique Carton date: Monday 2nd January 2012 text: I have an Olivetti M20 computer with two floppy drives and programs and documentation, anything I needed to have when I used it. Would consider selling it. - author: Dominique Carton date: Monday 2nd January 2012 text: I have an Olivetti M20 computer with two floppy drives and programs and documentation, anything I needed to have when I used it. Would consider selling it. - author: Dominique Carton date: Monday 2nd January 2012 text: I have an Olivetti M20 computer with two floppy drives and programs and documentation, anything I needed to have when I used it. Would consider selling it. - author: Steve (United States) date: Friday 11th March 2011 text: |- I have owned 2 M-20''s and learned to program on them.\ I still have 1/2 of one (missing the motherboard) and I''d love to have one again. I''m in the market if anyone wants to sell one to me. - author: Roelof Beverdam (Enschede, Netherlands) date: Sunday 26th September 2010 text: Hello, I too have a dual floppy M20. I also have a wealth of documentation and software - both original and (sometimes) copied - including less mainstream items, so to speak. Anyone familiar with Eightbit, Trans816, GPIB-interfacing or programming Numerical Controlled devices - just to name a few? It''s all (t)here - at least the manuals. I am searching for a working M20 emulator$ there is an entry in the MESS system, but without any real driver code. Best regards, Roelof - author: Davide Bucci (Italy) date: Thursday 5th May 2005 text: |- Hello, I have a M20 with several floppies, running PCOS. I have found user manuals on the Internet, but it would be cool to obtain more detailed informations regarding this computer. In particular, I am interested in how to access low level system calls in Basic, or developing small assembler routines.\ Best regards - author: Alejandro Corral (Granada, Spain) date: Tuesday 26th November 2002 text: |- Hello, I have an M20 with a few floppies, with PCOS and some programs. I have a thermal printer from olivetti too...\ Because lack of documentation I know very little about PCOS and the computer itself. I'm searching any type of documentation about PCOS, programs for it and MS-DOS 2 version adapted for M20 hardware. Best Regards oc_id: 611 source: url: https://web.archive.org/web/20230627021257/http://www.old-computers.com/museum/computer.asp?c=611 date: '2023-06-27' --- In 1972, Olivetti established in the U.S.A. (Cupertino), the Advanced Technology Centre (ATC), a research centre specialized in new technologies and office automation equipment design. During ten years the centre designed Olivetti typewriters, calculators, photocopiers, etc.... In 1980, the first Olivetti computer took form in Cupertino, and the M-20 computer was launched in March 1982. More than 50,000 units are estimated to have been shipped in the first year. The M20 was one of the very rare computers based on the Zilog Z8000, a 16 bits microprocessor very close to its 8 bits big brother the Z80. Like most of the computers designed before the IBM PC era, the M20 offered technical choices which made it totally incompatible with the rest of the micro world. The first proprietary M20 operating system, called PCOS (Professional Computer Operating System) was also very particular and didn't allowed files to be exchanged with other systems. Hopefully, MS-DOS V2.0, CP/M-86 and CP/M-80 would be later adapted to the specific M-20 hardware. Moreover, front of this compatibility problem, Olivetti developped a coprocessor board based on the 8086 chip, which offered M20 owners access to IBM PC software. The M20 came with a 12'' monochrome or colour custom built monitor. The international version had a grey plastic case, the Italian version had a brown one.