W742S819

·Operating voltage: 2.4V - 5.5V
·Dual-clock operation mode (Connect to 32768 Hz crystal only)
− Fslow oscillator : 32768Hz OSC
− Ffast oscillator : PLL ( Phase Lock Loop ) output enable
  Memory
− 12288 x 16 bits program ROM (including 48K x 4 bit look-up table)
− 1536 x 4 bits data RAM (including 16 nibbles x 16 pages working registers)
− 24 x 8 LCD data RAM
·24 input/output pins
− Port for input only: 1 ports/4 pins(RC)
− Input/output ports: 3 ports/12 pins(RA, RB & RD)
− High sink current output port for LED driving: 1 port /4 pins(RE)
− Port for output only: 1 ports/4 pins(RF)
·Power-down mode
− Hold function: no operation (excluding Fslow and Fosc oscillator)
− Stop function: no operation (Fslow and Fosc oscillator are stopped)
− Dual-clock slow operation mode: system is operated by 32768Hz (FOSC=Fslow and Ffast stopped)
·Five types of interrupts
− Four internal interrupts (Divider0, Divider1, Timer 0, Timer 1)
− One external interrupts (RC Port)
  LCD driver output
− 24 segments x 8 commons
− 1/8 duty, 1/3 bias driving mode by option code
− 16 level software LCD contrast adjusting
·MFP output pin
− Output is software selectable as modulating or non-modulating frequency
− Works as frequency output specified by Timer 1
  DTMF output pin (PLL should be enable in this function)
− Output is one channel Dual Tone Multi-Frequency signal for dialing
·Three OpAmps(Operational Amplifiers)
− Three general purpose OpAmps with positive inputs, negative inputs and outputs.
·Two built-in 14-bit frequency dividers
− Divider0: the clock source is the output of the Fosc-oscillator
− Divider1: the clock source is the output of the Fslow-oscillator
·Two built-in 8-bit programmable countdown timers
− Timer 0: one of two internal clock frequencies (FOSC/4 or FOSC/1024) can be selected
− Timer 1: with auto-reload function and one of three internal clock frequencies (FOSC, FOSC/64 or Fslow) can be selected by MR1 register; and the specified frequency can be delivered to MFP pin
·Built-in 18/15-bit watchdog timer selectable for system reset; enable the watch dog timer or not is determined by code option
·Build-in Power-on reset detested circuit
·Powerful instruction set: 1XX instructions
·16-levels subroutine (include interrupt) nesting

The W742S819 is a high-performance 4-bit micro-controller (C) that provides an LCD driver and three OpAmps. The device contains a 4-bit ALU, two 8-bit timers, two dividers (for two oscillators) in dual-clock operation, a 24 * 8 LCD driver, six 4-bit I/O ports (including 1 output port for LED driving), three OpAmps(Operational Amplifiers), and one channel DTMF generator. There are also five interrupt sources and 16-levels subroutine nesting for call subroutine or interrupt applications. The W742S819 operates on very low current and has two power reduction modes, that is the dual-clock slow operation and STOP mode, which help to minimize power dissipation.