GENERAL DESCRIPTION
EM73A88A is an advanced single chip CMOS 4-bit micro-controller. It contains 16K-byte ROM, 500-nibble RAM, 4-bit ALU, 13-level subroutine nesting, 22-stage time base, two 12-bit timer/counters for the kernel function. EM73A88A also equipped with 6 interrupt sources, 3 I/O ports (including 1 input port and 2 bidirection ports), LCD display (64x16), built-in sound generator and speech synthesizer can direct drive speaker. Its low power consumption and high speed feature are further strengten with DUAL, SLOW, IDLE and STOP operation mode for optimized power saving.

FEATURES
• Operation voltage : 2.2V to 4.8V.
• Clock source : Dual clock system. Low-frequency oscillator is 32 KHz Crystal or RC oscillator and high-frequency oscillator is a built-in internal oscillator (4.6 MHz).
• Instruction set : 107 powerful instructions.
• Instruction cycle time : 1.7µs for 4.6M Hz (high speed clock).
                                       244µs for 32768 Hz (low speed clock).
• ROM capacity : 16K x 8 bits.
• RAM capacity : 500 x 4 bits.
• Input port : 1 port (P0.0-P0.3), IDLE/STOP releasing function is available by mask option. (each input pin has a pull-up and pull-down resistor available by mask option).
• Bidrection port : 2 ports (P4, P8). IDLE/STOP release function for P8(0..3) is available by mask option.
• Built-in watch-dog-timer counter : It is available by mask option.
• 12-bit timer/counter : Two 12-bit timer/counters are programmable for timer, event counter and pulse width measurement mode.
• Built-in time base counter : 22 stages.
• Subroutine nesting : Up to 13 levels.
• Interrupt : External interrupt . . . . . . 2 input interrupt sources.
                   Internal interrupt . . . . . . 2 timer overflow interrupts, 1 time base interrupt.
                                                          1 speech interrupt.
• LCD driver : 64x16 dots, 1/16 duty, 1/5 bias with voltage multiplier.
• Sound effect : Tone generator and random generator.
• Speech synthesizer : 448K speech data ROM (use as 448K nibbles data ROM).
• PWM or current D/A : Output selection by mask option.
• Power saving function : SLOW, IDLE, STOP operation modes.
• Package type : Chip form 109 pins.