Olivetti M19

The machine came with three operating systems: MS-DOS 2.11 / 3.1, Concurrent DOS and UCSD p-System.^[1] It was capable of displaying graphics in standard CGA or Plantronics Colorplus mode (320x200 pixel with 16 colors and 640x200 with 4 colors), as well as a special 640x400 monochrome mode with an appropriate monochrome monitor.^[1]

The M19 was sold with two floppy disk drives (360 KB format). An internal SCSI controller card and accompanying hard drive could be fitted instead of the second floppy drive,^[8] with a 10 MB model advertised by Olivetti,^[1] and a 20 MB model advertised for the Acorn M19.^[4]

Since the system unit was designed to occupy a smaller area than many contemporary PC-compatible systems, a smaller form of internal expansion card was used. Olivetti advertised a selection of miniature cards including a second serial port, a BSC/SNA communications board, the SCSI controller card, and local area network cards.^[1] Acorn explicitly advertised Econet connectivity,^[4] whereas Olivetti advertised support for 10 NET connectivity, its own LAN technology,^[9] as well as "LAN economica", ostensibly Acorn's Econet. To use a standard "full size" expansion card, an external expansion box could be attached to the left-hand side of the computer by four machine screws.^{[citation needed]} This add-on was available in two different versions, one of which being able to provide power to the system in a colour monitor configuration,^[1] and this powered variant was bundled with Acorn's colour models.^[4] In a monochrome configuration using Olivetti's monitor, the system power was provided by the monitor, eliminating the need for a power supply and cooling fans inside the compact case of the machine.^[10]: 71

With only two internal expansion slots available, Olivetti incorporated various standard interfaces, specifically a serial port and Centronics parallel port together with the video circuitry and connectors, onto the motherboard itself, avoiding the need to dedicate up to three slots to provide such functionality.^[8] Other expansion and upgrade options included a mouse interface, television adapter for SCART-equipped televisions, and a "dual speed kit" offering a 8088 CPU with an operating frequency of 4.77 MHz or 8 MHz selectable by the user.^[4]

Paul Maynes, a technician at HBH Computers (one of Olivetti's dealerships in Durban) designed, and SA Signals Manufacturing (also of Durban) produced a bus extension card with a 90-degree bend (purportedly a world-first) that could accommodate a Seagate hard drive controller card. This allowed the second floppy drive to be removed and a 20 MB (later 40 MB) full-height hard drive installed in its place.^{[citation needed]}

In 1987 Olivetti introduced the word processor systems ETV 260 and ETV 500 based on the M19.^{[11][12][13][14]} While the ETV 500 was just a M19 accelerated to 8 MHz and equipped with two 3.5 inch 720 KB floppy drives,^[14] which used optionally an Olivetti ET series typewriter (usually a ET 112 or ET 116) as a serial-attached keyboard and daisy wheel printer, the ETV 260 was a fully-integrated word processor system with the M19 / ETV 500 accelerated mainboard mounted into a high speed 35 cps (characters per second) daisy wheel typewriter chassis, equipped with two 720 KB floppy drives or a single floppy drives plus an integrated 20 MB SCSI or MFM hard disk.^[12]

Both systems, ETV 260 and ETV 500, ran MS-DOS 3 and booted directly into Olivetti's own word processor software SWS - Secretary's Work Station,^[15] which could be easy used by people already familiar with Olivetti's ET series typewriters and older CP/M based ETV word processor systems (like the ETV 240, 250 or 350).

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  Olivetti M19 with external I/O box attached
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  Olivetti M19 rear view
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  Inside of the computer, with two 5 1⁄4-inch disk drives
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  Mainboard. An AMD P8259A Programmable Interrupt Controller is visible, together with a NEC V20 (μPD70108) main processor (instead of an Intel 8088)

• Olivetti M24
• Olivetti video typewriters
• Plantronics Colorplus