| 摘要 |
<P>PROBLEM TO BE SOLVED: To PWM-control a three-phase motor with accuracy by means of software processings. <P>SOLUTION: Output buffer registers 1 and 2 (18 and 20) are provided in correspondence with output set value registers 1 and 2 (17 and 19). A duty buffer register 14 is provided, in correspondence with a duty setting register 15. When a comparison circuit 1 or a comparison circuit 2 outputs a coincidence signal, the contents of output value setting registers 1 and 2 are outputted through gate circuits (G1 to G6), and a flag F1, and a PWMn output value is thereby varied. When the comparison circuit 1 detects coincidence, the values stored in the output buffer registers 1 and 2 and the duty buffer register at that time are read into the output value setting registers 1 and 2 and the duty setting register 15, and an interrupt signal (IRQn) is sent out to CPU. The CPU sets a value required in the next cycle on a corresponding buffer register (14, 18, 20) and then sends out an interrupt acknowledgment signal (ACKn). <P>COPYRIGHT: (C)2006,JPO&NCIPI |
