The same electrical device can be used in two modes, a simplex bus connection mode and a duplex bus connection mode, by collating signals output from two input and output ports for two electrical circuits in an electrical device with a comparator and detecting a fault in the electrical circuits in a...http://www.google.com.tw/patents/US5612946?utm_source=gb-gplus-share專利 US5612946 - Electrical device with input and output ports for changing the multiplex number of transmittal buses and system using the electrical device
