Hardware

Themechanical design of Hewlett-Packard's (HP) integral Personal Computer (PC) is based on the HP 85 Computer updating to an industry standard processor, a state-of-the-art 80-column ink-jet printer, a fast flexible-disc mass storage device, and a state-of-the-art 80-column by 24-line flatpanel display. It also retains the capability for removable I/O modules. The concept of an upright package selected to meet sound mechanical design goals and make the Integral PC easy to use. Many of the aspects of the human interface are addressed by the Integral PC's mechanical design, beginning with a detachable, low-profile keyboard. The high-contrast flatpanel display is mounted in a near vertical position (offset 5 degrees) for ease of viewing. The printer is mounted at the top of the package for easy access and paper handling. The whole system folds up into a compact, rugged, easily carried unit.

The Integral PC CPU, RAM, ROM, memory management, I/O buffering, system timing, and keyboard interface reside on one logic board, and all of the other peripheral circuitry (and 14 connectors) reside on another board. Each board is slightly smaller than a sheet of stationery (78 square inches). The interface between the boards contains data, address, and control signals. Each board has its own clock circuitry for reliability and ease of testing. An I/O board with two connectors for optional plug-in cards, a keyboard interface board with two connectors for HP Human Interface Link (HP-HIL) input devices, and the power supply board are the other printed circuit boards.

The Integral PC Graphics Processor Unit (GPU) is a special-purpose microprocessor designed to be used as a powerful dual CRT and electroluminescent display controller to provide the Integral PC a versatile, easy-to-use graphics subsystem with a bit-mapped display. The GPU is compatible with most commercially available CRT monitors and can rapidly manipulate lines, rectangles, windows, alpha characters, an automatic alpha cursor, and a graphics cursor. It also features a user-configurable screen size, monitor sync timing, multiple character fonts and fill patterns, and a display RAM interface.

The electroluminescent display based on thin film technology was developed by several manufacturers in cooperation with Hewlett-Packard during the development of the Integral Personal Computer. The display consists of three main parts or subassemblies: the electroluminescent panel, a driver assembly, and a control board. The driver assembly contains high-voltage switches connected to each row and column of the panel. This assembly receives logic control signals and high-voltage pulses from the control board and applies voltage to the display panel according to the desired pattern.

-- PeteJohnson^? - 07 Jan 2006