| 摘要 |
<p>PURPOSE:To minimize the number of terminals of a terminal processor, by constituting an input direction control circuit so as to set the direction of input and output, based on an address data assigned to each terminal processor. CONSTITUTION:An input/output circuit 60 switches whether a terminal is an input or an output terminal at input/output terminals 101-103 connected to an electric device or sensors 201-203, in response to an input/output logical level from the input/output direction control circuit 80. In this case, a means generating the input/output direction control signal is provided with a circuit 80 based on the address data given to an address set circuit 70 of each terminal processor 30 without being given the input/output direction data from the external devices of the terminal processor. Thus, input terminals exclusively used for the provision of data designating the direction of input/output externally are not required, the number of terminals of the processor 30 is minimized and the processor is formed in a small size.</p> |
