A friend of mine found this Olivetti M200 in landfill and gave it to me. In this way, this magnificent computer has been saved and joined my collection.
As soon as he arrived, the computer presented himself in pitiful condition: he was really dirty. Probably, it had been outdoors for some time, under the weather.
Cleaning of the Olivetti M200
I have summarized in 4 minivideos all the disassembly and cleaning operations I carried out, as well as the final test of the vintage computer.
Olivetti M200
The Olivetti M200 (Model BU 200-X) is a compact economic range desktop, produced in 1988. The monitor (model DSM 200) is physically attached to the computer case. The computer that was given to me did not have the keyboard. To try it, I had to connect an AT keyboard with 5 -pole DIN connector. The M200 Olivetti computer is equipped with a NEC V40 processor (UPD70208), which is compatible with the Intel 80188, with a 16 -bit architecture, but a data bus of only 8 bits. The RAM has a capacity of 640 KB.
Il sistema operativo di serie era MS DOS versione 3.30, ma può essere aggiornato con le versioni successive. Relativamente ai supporti di archiviazione dei dati, l'Olivetti M200 è dotato di un lettore di floppy disk interno, da 3.5", 720KB. E' possibile installare un secondo floppy disk drive. E' presente un hard disk da ben 20MB!
Internally, the motherboard is installed just below the monitor, at the level of the floppy disk drive. In the lower case there are two cards: one with 8 -bit ISA slots and one with the outdoor doors of the computer. In addition, there are the power supply and the hard disk drive.
Startup screen
The computer starts with the Resident Diagnostics: they are diagnostic programs resident in ROM, which verify the correct functioning of the computer. Diagnostic programs check the operation of: CPU (Nec V40), ROM, DMA, Interrupts, RAM, Timer, Optional ROM, floppy disk drive and hard disk.
Dopo il self test iniziale, il computer cerca un disco di avvio (dischetto floppy oppure disco rigido). Se non è presente alcun disco di boot, mostra un messaggio di errore: "Rom BASIC not available".
Technical characteristics of the Olivetti M200
CPU: NEC V40 (μPD70208), 16 bit
RAM: 640 KB (the RAM banks are physically soldered onto the motherboard under the monitor)
ROM: contiene il POST = Power On Self Test e il BIOS = Basic Input-Output System
Graphics: Integrated CGA graphics card, monochrome monitor included in the computer
Text mode: 80 columns x 25 rows
Graphics mode: 640 x 200 pixels
Audio: beep
Keyboard: external AT with 5-pole DIN connector
Supplied software: MS DOS version 3.30
Supporti di archiviazione: N. 1 floppy disk drive interno, 3.5", 720 KB, secondo floppy disk drive opzionale e N. 1 hard disk interno da 20 MB
Expansion ports, internal:
- No. 2 ISA 8 bit expansion slots on separate card
- No. 2 connectors for 34-pin floppy disk drives
- 44-pin hard disk connector
- Connector for connection to other computer cards
- Integrated monitor connector
Expansion ports, external:
- Keyboard AT DIN 5 poles, sides
- Parallel (DB25)
- Serial (DB25)
Dimensions and weight: currently not measured
Emulation
The M200 Olivetti computer starts with the MS DOS operating system. It is possible to emulate the MS-DOS environment with Dosbox (although Dosbox is an emulator for X86 systems).
Power supply
The power supply of the Olivetti M200 personal computer is internal. On the back of the computer, there is the IEC C14 power connector, where you can connect the mains power cable. My example is powered by 230 V alternating current 50 Hz.
Inside there is a flat cable that brings tensions to the motherboard and a 4 -pole Molex connector to power the hard disk.
The ignition switch is anterior. The monitor takes the 230V power supply directly from the computer via a rear cable.
Date of entry into the collection: 03/08/2024