The Testbed Devices of the Infrastructure for Ubiquitous Computing Project

The project constructed the three prototype devices. The Pad and Tab were funded partially by ARPA; the Board, the first project to be completed, was not. All prototypes were fully functional and in everyday use by PARC experimenters.

The Pad was a prototype pen computer. It was 9x11x1", had a four 4 hour battery life, and weighed 5 pounds. It used a Motorola 683xx processor with 4 MB ram running a unique real-time operating system. The Pad featured a PCMCIA slot, an electronic pen of our own design with a built-in microphone, a 640x480 4 level display, keyboard and serial ports. The Pad could communicate through infrared at 19.2kbs, through a unique nearfield radio at 240kbs, and through a 1Mbs tether which also supplied external power for operation and recharging. A complete Pad system also had a radio basestation that served as a recharging station and Ethernet gateway for the Pads.
The Tab was a prototype handheld computer. It was 2x3x0.5", had a 2 week battery life on rechargeable batteries, and weighed 7 oz. It used a Phillips 8051 processor with 128k NVRAM. It featured an external I2C external bus, a custom resistive touch screen, and a 128x64 mono display. A complete Tab system included an infrared basestation in the ceiling for LAN connectivity. The Tab project is consider by many to be the most significant of the three prototyping efforts.

Return to the Ubiquitous Computing home page.

Mark Weiser, 03/17/96 7:03:56 PM