| 摘要 |
PURPOSE:To improve resolution of operational frequency by storing a predetermined number of step data into a temporary memory means and outputting a PWM waveform, corresponding to the step data, from a real timer I/O port. CONSTITUTION:A memory section 12 is provided with a basic wave data based on a predetermined sine wave 11, a time data based on the basic wave data and a carrier wave 13 having a predetermined frequency, and a step data for reading out the basic wave data in order to combine the time data according to the operational frequency. A plurality of step data are provided for every frequency and a predetermined number of step data are read out according to the operational frequency. The step data are changed in step and the step data having modified frequency is finally stored in an inner memory RAM 10a. By such arrangement, resolution of the operational frequency can be improved and the frequency can be varied smoothly. |
