| 摘要 |
PURPOSE:To set parameter with simple hardware by detecting the value of a variable resistance as a time corresponding to the time constant of a time constant circuit, and obtaining the parameter value from the detected time and the content of memory that stores a parameter value of each time. CONSTITUTION:A resistance value R of a variable resistance 1a corresponds uniquely to the time constant (r) of a time constant circuit 1, and a time measuring circuit 2 measures time T corresponding to the time constant (r). Accordingly, the time T corresponds uniquely to the resistance value R of the variable resistance 1a. Parameter values corresponding to each value of the time T are stored beforehand in a storage circuit 3 and consequently, the resistance value R of the resistance 1a corresponds uniquely to the parameter value. Thus, for instance, parameter values corresponding to resistance values are graduated on the knob of the resistance 1a. When the resistance value of the resistance 1a is changed to a resistance value corresponding to a parameter value to be set, and time T corresponding to the time constant (r) of the circuit 1 is measured by the circuit 2, the parameter value stored in the circuit 3 is searched from the time T, and the parameter value is set. |
