| 摘要 |
PURPOSE: To reduce the failure of signal transmission by measuring voltage of a signal on a transmission line, and judging the transmission line to need termination resistance to connect the termination resistance with or disconnect the same from the transmission line. CONSTITUTION: This controller comprise a transmission line 8 that connects between an outdoor machine 1 and an indoor machine 7, and a microcomputer 2 including a software for controlling the outdoor machine 1 and an A/D converter. It comprises a transmission interface 3 for outputting a transmission signal outputted from the microcomputer 2 to an AMI encoded transmission line 8 and converting the signal to a signal format of the microcomputer 2 and inputting it to the microcomputer 2. It comprises termination resistance 5 connected with the transmission line 8 for modifying the waveform of the signal. The signal on the transmission line 8 is inputted into a controller, and voltage of the signal is read in a predetermined timing. The state of a signal waveform is detected from a predetermined judgment value, and provided the signal waveform on the transmission line 8 is abnormal, the termination resistance 5 is connected with the transmission line 8 to modify the signal waveform. |
