| 摘要 |
PURPOSE:To perform simultaneous processing of a transmission wave output processing and an arbitrary processing spuriously by setting a reference frequency in the initialization of a program, and setting output pulse width and an interruption cycle in an interruption processing at the time of outputting a transmission wave. CONSTITUTION:Original oscillation from an oscillation circuit 101 is converted to a carrier by a carrier generation circuit 102. At this time, the duty and the frequency division ratio of the carrier from the original oscillation is set by setting a value on a register 105 in software by a microcomputer. Furthermore, a reference cycle signal 152 synchronized with a modulation cycle is generated at a reference cycle generation circuit 104, and an output control signal 153 to control an output gate 110 is generated at an output pulse width generation circuit 106 based on the above- mentioned signal, then, pulse modulation is performed at the output gate 110. Cycle width is set at the register 105, and the number of one time of output cycles of the carrier is set at a register 107. A circuit 108 generates an interruption signal 154, and the microcomputer realizes the pulse modulation by setting the number of cycles to the execution of interruption at the registers 107 and 109, then, the transmission wave 155 is generated. |
