Method for Detecting Floating Potentials on Transmission Lines
Original Publication Date: 1988-Jun-01
Included in the Prior Art Database: 2005-Feb-15
Open transmission lines cause errors in data transmission. A line may be open because it has been interrupted or because no circuit card is connected to it in the receiving device. Because of the stray capacitance of the line, a signal written thereon is maintained for a certain time, so that a subsequent read operation reads this signal. Therefore, an open line cannot be detected by check bits. The method described in this article allows the detection of open transmission lines by subsequent write and read operations, using appropriate bit patterns. It is particularly useful where self-configuration of a central computer and several peripheral devices are used and a different pattern of circuit cards is found in each peripheral device. The method comprises the following steps: 1. A defined signal is written on the line.