SYSTEM AND METHOD FOR OPTICALLY TRANSMITTING SERIAL DATA

摘要

Described herein is a system for transferring a binary data stream in a serial edge-based transmission format between a computer (100) and a portable device (104) such as the Timex3 DataLink watch. In the edge-based format expected by the DataLink watch, individual data bits have first and second binary values which are represented by the presence or absence of signal edges at mark times (32) which occur at a pre-selected bit rate. The system includes a computer having a digital output line which can be turned on and off by the computer at any time. The computer also has an internal timer (130) which is programmed to generate timing signals at a frequency which is an integer multiple n of the pre-selected bit rate. A wand (108) with an LED (144) is operably connected to a selected digital output line from a parallel interface (126) or a serial interface (128), so that the computer can switch the LED on and off at any time through the digital output line.