W742S81A Datasheet, PDF (1/47 Pages) Winbond – 4 BIT MICROCONTROLLER

W742S81A
4-BIT MICROCONTROLLER
1. GENERAL DESCRIPTION
The W742S81A is a high-performance 4-bit microcontroller (µC) that provides an LCD driver. The device
contains a 4-bit ALU, two 8-bit timers, two dividers (for two oscillators) in dual-clock operation, a 40 × 4
LCD driver, six 4-bit I/O ports (including 1 output port for LED driving), and one channel DTMF
generator. There are also five interrupt sources and 16-levels subroutine nesting for interrupt applications.
The W742S81A 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.
2. FEATURES
• Operating voltage: 2.4V – 5.5V
• Dual-clock operation or single-clock operation (By option)
• Main-oscillator
− Connect to 3.58MHz crystal or 400KHz that can be selected by option code
− Crystal or RC oscillator can be selected by code option
• Sub-oscillator
− Connect to 32768 Hz crystal only
• Memory
− 16384 x 16 bits program electrical erasable EPROM (including 64K x 4 bit look-up table)
− 2048 x 4 bits data RAM (including 16 nibbles x 16 pages working registers)
− 40 x 4 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 port/ 4 pins(RF)
• Power-down mode
− Hold function: no operation ( main-oscillator and sub-oscillator still operate)
− Stop function: no operation ( main-oscillator and sub-oscillator are stopped)
− Dual-clock slow operation mode: system is operated by the sub-oscillator (FOSC=Fs and Fm is
stopped)
• Five types of interrupts
− Four internal interrupts (Divider0, Divider1, Timer 0, Timer 1)
− One external interrupts (RC Port)
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Publication Release Date: March 2003
Revision A1