R

EMDB6812

Copyright © 2004, EM Microelectronic-Marin SA

11

www.emmicroelectronic.com

4.

APPENDIX : DEMO APPLICATION

4.1 INTRODUCTION

The goal is to run a typical User Front-end Controller which allows to keep the power consumption

in standby mode at a minimum while RTC, Timer and Keyboard- handling are still fully working.

Furthermore this controller shall serve as Power-On Reset, Battery Level Detector and IO

Extension.

Note:

o = output

i = input

4.2 ARCHITECTURE

4.2.1

Features

The Microcontroller has the following functions:

•

Power-On Reset

•

Serial Interface to the Host (Software UART)

•

RTC Timer

•

32kHz digital clock output to the host

•

Power-Up of the Host

•

Battery Level Detector

•

Auxiliary Outputs

•

Key Inputs

4.3 FUNCTION

When powering up the system, the Microcontroller is reset automatically, as soon as the Reset-

Threshold of its Power-On-Reset is reached. It will then initialize itself, Power-Up the Host, and

enable the 32kHz Source which can be used by the Host. From now on, the Host can send

commands via the serial interface to the Microcontroller to get/set the corresponding information.

Available commands are:

HOST_PWR

HOST_32k

HOST_TX

HOST_RX

Microcontroller

SW-

UART

32kHz

CTRL

Keys

PWM

SVLD

RTC /

Timer

Host

Simulated by PC

Aux

Outputs