R

EMDB6812

Copyright © 2004, EM Microelectronic-Marin SA

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PowerDown, Powers down the Host (eg. if battery level too low)

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GetTime, Read the Time from the RTC

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SetTime, Set the RTC

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SetTimer, Set a Timer. As soon as it reaches zero, the Host is powered up.

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SetPWM (eg. PWM Outputs, can be used eg. for Led backlight)

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SetOutput, Set the Aux outputs

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GetKeys, Get the Key States

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GetEOL, get the Battery Level

As soon as the Microcontroller detects that a key has been pressed, it sends the new key-State

automatically to the Host!

4.4 SOFTWARE

The Microprocessor has a Software-Half-Duplex UART incorporated which runs at 2400bps with 1

start-bit, 8 databits and 1 stopbit.

Via this UART the following commands can be executed:

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PowerDown

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GetTime

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SetTime

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SetTimer

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SetPWM (eg. For Led backlight)

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SetOutput

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GetKeys

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GetEOL

4.4.1

CPU operation Modes

The 32kHz Oscillator is always on for keeping accurate RTC timing

The CPU clock is switched off during Idle mode

During UART Reception/Transmission the Microcontroller uses the RC Oscillator, which

runs at approximately 1MHz

4.4.2

Main loop

PowerOn Reset

Init

RX on UART?

no

Enable Host

Send echo

Valid command?

Execute Cmd-Routine

no