GENERAL DESCRIPTION

The W741L260 is a high-performance 4-bit microcontroller (mC) with an LCD driver. The device contains a 4-bit ALU, two 8-bit timers, two dividers, a 32 ´ 4 LCD driver, and five 4-bit I/O ports (including one high sink current output port). There are also five interrupt sources and 8-level subroutine nesting for interrupt applications. The W741L260 has one power reduction mode to help minimize power dissipation.

The W741L260 has two oscillator circuits and can work in dual-clock or single-clock operation mode. It is suitable for handheld games, watches, clocks, speech synthesis LSI controllers, and other products.

FEATURES

· Operating voltage: 1.2V to 1.8V (LCD drive voltage: 3.0V, or 4.5V)

· Operating frequency up to 1 MHz

· Crystal/RC oscillation circuit selectable by code option for system clock

· 32.768 KHz crystal oscillation circuit for sub-oscillator

· Only low-frequency clock (32.768 KHz) for crystal mode

· Memory

   - 2048 x 16 bit program ROM (including 2K ´ 4 bit look-up table)

   - 128 x 4 bit data RAM (including 16 working registers)

   - 32 x 4 LCD data RAM

   · 21 input/output pins

   - Ports for input only: 2 ports/8 pins

   - Input/output ports: 2 ports/8 pins

   - Port for output only: 1 port /4 pins (high sink current)

   - MFP output pin: 1 pin (MFP)

· Power-down mode

   - Hold function: no operation (except for oscillator)

· Five types of interrupts

   - Four internal interrupts (Divider 0, Divider 1, Timer 0, Timer 1)

   - One external interrupt (Port RC)

· LCD driver output

   - 32 segment x 4 common

   - Static, 1/2 duty (1/2 bias), 1/3 duty (1/2 or 1/3 bias), 1/4 duty (1/3 bias) driving mode can be selected

   - LCD driver output pins can be used as DC output ports; selectable by code option

· MFP output pin

   - Output is software selectable as modulating or nonmodulating frequency

   - Works as frequency output specified by Timer 1

· Two built-in 14-bit clock frequency divider circuit (divider 0 and divider 1)

· 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: includes an auto-reload function; and one of two internal clock frequencies (FOSC or FOSC/64) can be selected or falling edge of pin RC.0 can be selected (output through MFP pin)

· Built-in 18/14-bit watchdog timer selectable for system reset

· Powerful instruction set: 118 instructions

· 8-level subroutine (include interrupt) nesting

· Up to 4 mS instruction cycle (with 1 MHz operating frequency)

· Packaged in 80-pin QFP