Abstract: A computer system that provides for transparent plugging and unplugging of a keyboard independent of system operation. A virtual keyboard device communicates with the system keyboard controller when no keyboard is plugged. The virtual keyboard device provides appropriate responses to inquiries from the operating system during startup, allowing the system to boot without an actual keyboard being present. When a keyboard is plugged, its presence is detected and it is configured by a virtual keyboard controller. The newly configured keyboard is then coupled to the system keyboard controller. On unplug, the lack of a keyboard is detected by monitoring the power supply to the keyboard, whereupon the virtual keyboard is again coupled to the system keyboard controller.

Abstract: A floating point system and method according to a format that includes a sign bit, an exponent part having a plurality of bits, and a fraction part having a plurality of multi-bit blocks, wherein floating point operation is based on block shifts of the fraction part, with each shift of one block associated with an increment or decrement of the exponent part by one count. This format illustrated is implemented as a format suitable for the accuracy greater than the IEEE 32-bit floating-point format, and is intended to be implemented in machines having byte-wide (8 bit) data streams. The preferred format consists of a sign bit, 7 exponent bits and 4 fraction bytes of eight bits for a total of 40 bits. This format and implementation allows floating-point commands to be executed in a fixed small number of cycles, thus advancing the capabilities of doing floating-point arithmetic on a SIMD machine.

Abstract: The present invention relates to a computer system and more particularly to a computer system which allows option controller cards for various input/output (I/O) devices to be added on the motherboard at minimum cost.