Design Contest Flash Innovation 2003

RS-232-to-RS-485 Communications Multiplexer

Motorola Flash Innovation 2003 – Design Contest
Distinctive Excellence

Hua Zhou


The multiplexer provides eight RS-485 communications ports using one RS-232-to-RS-485 conversion circuit. A 68HC908QY1 controls eight analog switches and builds connections between a real RS-485 communications port and any one of the eight virtual ports. You can control the target channel manually, let the MCU do it automatically, or use a specially designed program running on the PC. An LCD displays the statuses.

Supporting Files

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Contest Ended: June 30, 2003

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