Oki Electric Industry MSM80C31F
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.GENERAL DESCRIPTION
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)
● 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 used arbitrarily (by SP specified)
● Two CPU power-down modes (1) Idle...