General Description

The Enhanced I/O MCUs are a series of 8-bit high performance, RISC architecture microcontrollers specifically designed for a wide range of applications. The usual Holtek microcontroller features of low power consumption, I/O flexibility, timer functions, oscillator options, power down and wake-up functions, watchdog timer and low voltage reset, combine to provide devices with a huge range of functional options while still maintaining a high level of cost effectiveness. The fully integrated system oscillator HIRC, which requires no external components and which has three frequency selections, opens up a huge range of new application possibilities for these devices, some of which may include industrial control, consumer products, household appliances subsystem controllers, etc.

Features

CPU Features

Operating voltage:

fSYS= 4MHz: 2.2V~5.5V

fSYS= 8MHz: 3.0V~5.5V

fSYS= 12MHz: 4.5V~5.5V

Up to 0.33s instruction cycle with 12MHz system clock at VDD= 5V

Oscillator types:

External high freuency Crystal -- HXT

External RC -- ERC

Internal high frequency RC -- HIRC

External low frequency crystal -- LXT

Three operational modes: Normal, Slow, Sleep

Fully integrated internal 4MHz, 8MHz and 12MHz oscillator requires no external components

Watchdog Timer function

LIRC oscillator function for watchdog timer

All instructions executed in one or two instruction cycles

Table read instructions

63 powerful instructions

Up to 4-level subroutine nesting

Bit manipulation instruction

Low voltage reset function

Wide range of available package types

Peripheral Features

Up to 26 bidirectional I/O lines

Software controlled 4-SCOM lines LCD COM driver with 1/2 bias

External interrupt input shared with an I/O line

Up to two 8-bit programmable Timer/Event Counter with overflow interrupt and prescaler

Time-Base function

Programmable Frequency Divider - PFD