The S3C7515/P7515 single-chip CMOS microcontroller has been designed for high-performance using Samsung's newest 4-bit CPU core, SAM47 (Samsung Arrangeable Microcontrollers). The S3P7515 is a microcontroller which has 16-kbyte one-time-programmable EPROM but its functions are same to S3C7515. With its DTMF generator, 8-bit serial I/O interface, and versatile 8-bit timer/counters, the S3C7515/P7515 offers an excellent design solution for a wide variety of telecommunication applications. Up to 55 pins of the 64-pin SDIP or QFP package can be dedicated to I/O. Seven vectored interrupts provide fast response to internal and external events. In addition, the S3C7515/P7515's advanced CMOS technology provides for low power consumption and a wide operating voltage range.