| 摘要 |
PURPOSE:To relieve the load on a microprocessor by providing an ST (control tone) signal circuit comprising a hardware and giving its command by the microprocessor. CONSTITUTION:A microprocessor 1-4 outputs a STOP signal designating ON/ OFF of ST signal transmission, a CON signal sending continuously the ST signal, an ON1 signal designating a 1800ms timer signal transmission, an ON4 signal designating a 400ms timer signal transmission, an ON5 signal designating a 50ms timer signal transmission and a system clock or the like to a start control section 1-7-1. The control section 1-7-1 sends a signal to a count section 1-7-2 and a stop control section 1-7-3 and outputs a PLS signal (ST transmission enable signal) controlling the transmission of the ST signal and an STIRQ signal generating an ST signal transmission end interrupt to the microprocessor 1-4. |
