| 摘要 |
PURPOSE:To offer an analog input/output device which can be operated efficiently and also whose cost is low by using a digital-analog converter for an analog input/output, too, and forming an analog input device and same output device as one body. CONSTITUTION:As for an operation of an analog input, a switch 11 is closed and switch 12 is opened by a controlling circuit 10, and as for an input of a digital- analog converter 4, an output of a comparing register 1 is selected successively by a selector 3, and the output is compared with the analog input by one bit each from the uppermost bit to the lowest bit by a comparator 7. When it is larger than an analog input signal, a digital output corresponding to the analog input is sent out by moving successively the comparing register 1 to the following bit. As for an operation of an analog output, the switch 11 is opened and the switch 12 is closed by the controlling circuit 10, and an output of a register 2 to which a digital input is set is selected by the selector 3, converted to an analog value by the digital-analog converter 4, and outputted to the outside.
|
