*** Welcome to piglix ***

AT&T 6300

Olivetti M24
Original Olivetti M24
Manufacturer Olivetti
Type Personal computer
Release date 1983; 34 years ago (1983)
Discontinued 1987
Operating system MS-DOS
CPU Intel 8086 @ 7.18 MHz
Memory 128 KB or 256 KB (expandable to 640 KB)
Successor Olivetti M240

The Olivetti M24 is a computer that was sold by Olivetti in 1983 using the Intel 8086 CPU.

The system was sold in the United States under its original name by Docutel/Olivetti of Dallas.AT&T and Xerox bought rights to rebadge the system as the AT&T PC 6300 and the Xerox 6060 series, respectively. (AT&T owned 25% of Olivetti around this time.) The AT&T 6300, launched in June 1984, was AT&T's first attempt to compete in the PC compatible market.

Contrary to other PC clones of that era, the M24 was highly compatible with IBM PC. One of its characteristics was the use of the more powerful 7.18 MHz Intel 8086 CPU rather than the 4.77 MHz Intel 8088 used in IBM's own PC XT while allowing the installation of the 8087 math co-processor.

The system was designed "split-level", with the motherboard screwed onto the underside of the computer case and connected to the ISA bus backplane in the top section of the case via the video card which, rather than occupying an ISA slot, has two female edge connectors and plugs onto the ends of both the motherboard and the backplane, doubling as a bridge between them. The M24 has seven 8-bit ISA slots, as were standard for its time, but two of the slots have proprietary second connectors to accept Olivetti 16-bit cards.

The initial release of the AT&T 6300 had either one or two 360k 5.25" floppy drives; a hard disk was not offered. In 1986, AT&T began offering 3.5" 720k floppies and 20MB hard disks. The Xerox 6060 came standard with a single 360k 5.25" drive and a 20MB hard drive.

6300s made in 1986-1987 have BIOS Version 1.43 which added proper support for 3.5" floppies and fixed a number of bugs. As with all contemporary systems, a BIOS upgrade required a physical chip replacement, which AT&T provided for $35.

The M24/6300 had an enhanced CGA video card which, in addition to standard 200-line CGA modes, also supported an additional 640x400x2 mode (text mode was 400 lines and had 8x16 character boxes). It required a proprietary dual-sync monitor. The 640x400 graphics mode received a moderate level of support from software developers, mostly in applications (Earl Weaver Baseball is however an example of a game that can use it). Some plasma portables from Compaq and other manufacturers also copied the M24/6300's graphics hardware.


...
Wikipedia

...