Keyboard, Mouse

The Personal System/2 or PS/2 was IBM's second generation of personal computers. The PS/2 line, released to the public in 1987, was created by IBM in an attempt to recapture control of the PC market by introducing an advanced proprietary architecture. more...

Although IBM's considerable market presence ensured the PS/2 would sell in relatively large numbers, the PS/2 architecture ultimately failed in its bid to return control of the PC market to IBM. Due to the higher costs of the closed architecture, customers preferred competing PCs that extended the existing PC architecture instead of abandoning it for something new. However, many of the PS/2s innovations, such as the 72 pin SIMM, the PS/2 keyboard and mouse ports, and the VGA video standard, went on to become standards in the broader PC market.

Technology

IBM's PS/2 was designed to remain software compatible with their PC/AT/XT line of computers upon which the booming PC clone market was built, but the hardware was quite different. PS/2 had two BIOSes. One was named ABIOS (Advanced BIOS) with which OS/2 operating system was running on PS/2. The other was named CBIOS (Compatible BIOS) which was prepared in order for PS/2 to be software compatible with the PC/AT/XT.

Micro Channel Architecture

The IBM Personal System/2 line introduced the Micro Channel Architecture (MCA for short) which was technically superior to the ISA bus and allowed for higher speed communications within the system.

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