HP-01

The Hewlett-Packard HP-01 was the first calculator wristwatch ever manufactured and sold to the public by Hewlett-Packard. The HP-01 used 9 light-emitting diodes (LEDs) for its digital display. Introduced in 1977 at the height of the LED watch craze, five models were available, two gold filled models and three stainless models. Prices were from $650 to $850 which was quite a lot of money back in 1977. Most of the 28 buttons on the HP-01 were recessed and were designed to be depressed with a stylus. The production was stopped by the end of 1979.

The HP-01 was unique not only as the only Hewlett-Packard watch but due to these unique features:

• Datatype for time, date, and time interval, and the ability to perform mathematics on these datatypes.
• A stopwatch that allows the stopwatch time to be multiplied or divided by a constant, and continuously display the results. This was referred to as a "Dynamic Rate Calculation."
• The HP-01 was Hewlett-Packard's first algebraic calculator. Prior to the HP-01, all Hewlett-Packard calculators used Reverse Polish notation. In later years,some HP calculators used a mixture of both.

External links

• LED-FOREVER.COM - The most detailed website on the HP-01 and HP-02
• Hewlett-Packard Official Page on the HP-01
• December 1977 Hewlett-Packard Journal - Entire issue dedicated to the HP-01
• The famous HP-01 LED Calculator Watch