| 摘要 |
<p>PURPOSE:To reduce the number of optical fibers and electric wires by connecting control units in a ring form by the optical fibers, providing a parallel/serial or serial/parallel conversion circuit to the input/output section of an electric signal and connecting it with devices by one electric wire. CONSTITUTION:In turning on an operation switch, a command signal is fed to one of input terminals 52 of a switch control circuit 48 and given to an input buffer 54. A CPU 60 reads the signal, a parallel/serial conversion circuit 58 converts it into a multiplexing serial signal and sends the signal to the 1st control unit 2. The CPU 60 of the unit 2 reads periodically the serial signal via a serial/parallel conversion circuit 44, the conversion circuit 42 converts again it into the serial signal, which is converted into an optical signal by an electrooptic converter 40 and sent to an optical fiber 8. The optical signal sent to the 3rd control unit 6 is converted into an electric signal by a photoelectric converter 41, a CPU 36 reads the signal to share it into a data to a control object load of the unit 6 and a data to be transferred to the 2nd and 1st control units 4, 2 and the result is outputted to an output buffer.</p> |
