| 摘要 |
<p>PURPOSE:To set or reset an output terminal without requiring a special circuit, by so constituting that the bit processing of an output port is executed by making use of an operation logical unit. CONSTITUTION:In case a0 is set in a state that output terminals of an A port are 0110, a data outputted to the A port is inputted to one terminal of an operation logical unit 14 through a bus line 12 by setting a port designating signal SPa and a signal LIO to ''1''. On the other hand, to the other input of the unit 14, 0001 is provided from a decoder 20, the operation is executed by operation contorl signals C1-C3, and 0111 is sent out to a line 12. The data 0111 on the line 12 is outputted to the A port through a storage circuit 23, accordingly, the terminal a0 becomes ''1'' and is set. Subsequently, in case a terminal b1 is set or inverted in a state that output terminals b0-b3 of a B port are 0110, a data of the terminals b0-b3 is provided to the unit 14 in the same way, a necessary operation is executed, and said data is sent out to the terminals b0-b3, by which the processing is executed.</p> |
