| 摘要 |
PURPOSE:To decrease the number of connection lines and to make the cost and maintenance more advantageous than those of a conventional system, by employing ¦tree¦structure even for the connection system of input data lines of a sequence controller. CONSTITUTION:An address 4 is specified with starting four system clocks and an address signal. Thus, a branch box 4 is specified and the following system clocks and address signals are supplied via only the branch box 4 according to lower priority. When the following four system clock pulses specify and address 2, a branch box 42 is specified. When an address 6 is assigned corresponding to the further following system clock pulses, a sensor 426 is specified. In the process of specifying those addresses 4, 2 and 6, the data lines of the branch boxes 4 and 42 conduct between a control unit CU and the sensor 426, so the output value of the sensor 426 is then read in the control unit CU. |
