MSM80C31F

E2E1037-19-41 ¡ Semiconductor MSM80C31F/MSM80C51F ¡ Semiconductor CMOS 8-Bit Microcontroller This version: Mar. 1995 MSM80C31F/80C51F GENERAL DESCRIPTION The OKI MSM80C31F/MSM80C51F microcontroller is a low-power, 8-bit device implemented in OKI's silicon-gate complementary metal-oxide semiconductor process technology. The device includes 4K bytes of mask programmable ROM (MSM80C51F only), 128 bytes of data RAM, 32 I/O lines, two 16-bit timer/counters, a five-source two-level interrupt structure, a full duplex serial port, and an oscillator and clock circuitry. In addition, the device has two software selectable modes for further power reduction — Idle and Power Down. Idle mode freezes the CPU's in-struction execution while maintaining RAM and allowing the timers, serial port and interrupt system to continue functions. Power Down mode saves the RAM contents but freezes the oscillator causing all other device functions to be inoperative. FEATURES Low power consumption by 2 mm silicon gate CMOS process technology Fully static circuit Internal program memory : 4K bytes (MSM80C51F) www.DataSheet4U.com External program memory space : 64K bytes Internal data memory (RAM) : 128 bytes External data memory (RAM) space : 64K bytes I/O ports : 8-bit ¥ 4 ports Two 16-bit timer/counters Multifunctional serial port (UART) Five interrupt sources (Priority can be set) Four sets of working registers (R0-7 ¥ 4) Stack : Internal data memory (RAM) 128-byte area can be...