assig final (1)

7/30/2019 Assig Final (1)

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EMBEDDED SYSTEM DESIGN

SOFTWARE FOR SIX CHANNEL CONTROLLERBASED ON CLOCK TIME

By

N.Nagaraju(CDS12M004)

Rahul sinha(CDS12M006)


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OBJECTIVE:

Develop software for a 6 channel controller which can be individuallyswitched on and off based on clock time. Two channels can be sequenced

together.


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SIX CHANNEL CONTROLLER

Fansis FC-525 6-Channel Multi Fan Controller Reeven Six Eyes RFC-01 6 Channel Fan Controller


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SOFTWARE REQUIREMENTS

1.CLOCK

2.SIX CHANNEL CONTROLLER

3.INTERRUPTS


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Theoretically, One Clock Is Enough

A clock is a square wave signal whose edges trigger hardware

A clock may be generated by various sources of pulses, e.g. crystal

But, systems have conflicting requirements

Low power, fast start/stop, accurate


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Different Requirements for Clocks

Different clock sources also have differentcharacteristics

Crystal: accurate and stable (w.r.t. temperature or

time); expensive, delicate, drawing large current,external component, slow to start up or stabilize

Resistor and capacitor (RC): cheap, quick to start,integrated within MCU and sleep with CPU; poor

accuracy and stability Ceramic resonator and MEMS clocks in between

Need multiple clocks


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Clocks in MSP430

MSP430 addresses the conflicting demandsfor high performance, low power, precisefrequency by using 3 internal clocks, whichcan be derived from up to 4 sources Master clock (MCLK): for CPU & some peripherals,

normally driven by digitally controlled oscillator(DCO) in megahertz range

Subsystem master clock (SMCLK): distributed toperipherals, normally driven by DCO

Auxiliary clock (ACLK): distributed to peripherals,normally for real-time clocking, driven by a low-frequency crystal oscillator, typically at 32 KHz


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Clock Sources in MSP430

Low- or high-frequency crystal oscillator, LFXT1:

External; used with a low- or high frequency crystal; anexternal clock signal can also be used; connected toMSP430 through XIN and XOUT pins

High-frequency crystal oscillator, XT2:

External; similar to LFXT1 but at high frequencies

Very low-power, low-frequency oscillator, VLO:

Internal at 12 KHz; alternative to LFXT1 when accuracy of acrystal is not needed; may not available in all devices

Digitally controlled oscillator, DCO:

Internal; a highly controllable RC oscillator that starts fast


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Clock Sources in MSP430

Low- or high-frequency crystal oscillator, LFXT1:

External; used with a low- or high frequency crystal; anexternal clock signal can also be used; connected toMSP430 through XIN and XOUT pins

High-frequency crystal oscillator, XT2:

External; similar to LFXT1 but at high frequencies

Very low-power, low-frequency oscillator, VLO:

Internal at 12 KHz; alternative to LFXT1 when accuracy of acrystal is not needed; may not available in all devices

Digitally controlled oscillator, DCO:

Internal; a highly controllable RC oscillator that starts fast


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From Sources to Clocks

Typical sources of clocks: MCLK, SMCLK: DCO (typically at 1.1 MHz)

ACLK: LFXT 1 (typically at 32 KHz)


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INTERRUPTS

Reaction to something in I/O (human, comm link)

Usually asynchronous to processor activities

interrupt handler or interrupt service routine (ISR)

invoked to take care of condition causing interrupt Change value of internal variable (count)

Read a data value (sensor, receive)

Write a data value (actuator, send)


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Relay 1

Msp

430

Power

Relay 2

Relay3

Relay4

Relay5

Relay6

Device1

Device 2

Device3

Device 4

Device 5

Device 6


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Start

Set the Timer based on

real time(in built timer)

After 5 minutes First channel

is set for output p2.1

After 10 minutes First channel is

set for output p2.2


set for output p2.3


set for output p2.4

After 25 minutes First channel is setfor output p2.5

After 30 minutes First channel is set

for output p2.6

Close


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#include

#include

#include /***** Function To Initialize Ports*****/

int n=0;

void init_ports()

{

DDRB = 0xFF;

PORTB = 0x00;

}

/***** Function To Initialize Interrupts*****/

void init_interrupts(){

cli(); //Disable Global Interrupts

GICR =(1


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if(n==1)

{

PORTB = 0x03;

n++;

_delay_ms(100);

}

else

if(n==2)

{

PORTB = 0x05;

n++;_delay_ms(100);

}

else

if(n==3)

{

PORTB = 0x00;

n=0;

_delay_ms(100);

}

_delay_ms(100);

}


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/***** Main Function *****

int main(void)

{

init_ports();

while(1)

{

init_interrupts();

}

}


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THANK YOU

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