General Description
The EM78869 is an 8-bit RISC type microprocessor with low power, high speed CMOS technology. Integrated into the single chip are on chip watchdog (WDT), RAM, ROM, programmable real-time clock/counter, internal interrupt, power-down mode, LCD driver, and tri-state I/O. The EM78869 provides a single chip solution for designing DATA-BANK of message display.

 Features
CPU
Operating voltage range:2.2V ~ 5.5V
„Operating temperature range:–20°C ~ +70°C.
32.768KHz Crystal/RC oscillation circuit selected by code option for system clock
144 byte general purpose register
640 x 8 bits on-chip data RAM
8K x 13 on-chip mask type program ROM.
Up to 29 bi-directional tri-state I/O ports
8-level stack for subroutine nesting
8-bit real time clock/counter (TCC)
Programmable free running on-chip watchdog timer
Port key scan function
Operation mode:a) Normal mode; b) Green mode; c).Idle mode; d) Sleep mode
Input port wake-up function (Port 9)
7 interrupt sources:
  •4 external (INT0 ~ INT3)
  •3 internal (one TCC timer overflow interrupt + two 8-bit counters overflow interrupt)
64-pin chip form (EM78869)

APPLICATIONs
Data Bank
Message display box
Scientific calculator