Patent ID: 6014716
Filing Date: 2000-01-11
Classification: G06F

Abstract:
A bidirectional communication recognition method for a first device in a communication system for transmitting data in a forward direction from the first device to a second device over parallel data lines of a parallel interface, and transmitting data in a reverse direction from the second device to the first device over the parallel data lines, the method comprising:writing specific data to a data register provided in the first device, which outputs data written during forward direction transmission as parallel signals to the parallel data lines,reading contents of the data register, andcomparing the written specific data with the read contents to determine whether the read contents and the written data are different,if the read contents and the written data are determined to be different, recognizing that bidirectional communication of the first device and the second device at a predetermined system over the parallel data lines is possible without operator intervention,if the read contents and the written data are determined to be identical recognizing that the bidirectional communication is not possible without operator intervention, andwhen the read contents and the written data are determined to be different, sending a data transmission request and a notification indicating that data line reverse direction transmission is possible from said first device to said second device.