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Controlling real world with c

WAP to toggle led connected to pin 1 of port 1

#include

void delay(unsigned int);

sbit led=P1;

void main(){

P1=0X00;

while(1)

{

led=0xff;

delay(50);

led=0x00;

delay(50);

}

}

void delay(unsigned int x)

{

unsigned int i,j;

for(i=0;i

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Switch programming

A switch is interfaced to P1.0. If the switch is

pressed toggle the port 0, else toggle the

port 2.

#include

void delay(unsigned int);

sbit SWITCH=P1^0;

p0=0x00; p2=0x00;void main()

{

SWITCH=1;

while(1)

{

if (SWITCH ==1)

{P0=0xff; delay(500);

P0=0x00; delay(500);

}

else

{P2=0xff; delay(500);P2=0x00; delay(500);

}}}

void delay(unsigned int x)

{unsigned int i,j;

for(i=0;i

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sbit reset=P1^2;

void delay(unsigned int);

void main()

{reset=1;

while (1)

{ if(reset==1)

{Pin1=1; Pin2=0;

delay(1000);}

else

{Pin1=0; Pin2=1;

delay(1000);}

}}

void delay(unsigned int time)

{

unsigned int i,j;

for(i=0;i Backward

Key 4 -> Left TurnKey 6 -> Right Turn

Key 5 -> Stop

Keypad is interfaced to port 1 and motor driver

is connected to port2

#include

unsigned char i;

void main()

{

P1=0xFF; // configure port 1 as input

P2=0x00; // configure port 2 as outputwhile(1)

{ i=P1;

}

switch(i)

{

case 2: P2=0x05; break;

case 4: P2=0x04; break;

case 5: P2=0x00; break;

case 6: P2=0x02; break;

case 8: P2=0x0A; break;

default: break;

}}

LEDs are connected to bits of P1 and P2. Write

an 8051 C program that shows

the count form 0 to FFH on the LEDs.

#include

#define LED P2

void main(){

P1=00;

LED=0;

for(;;)

{

P1++;

LED++;

}

}

Interfacing Stepper Motor

Fig. shows how to interface the Stepper Motor to

microcontroller. As you can see the stepper motor is

connected with Microcontroller output port pins

through a ULN2003 array. So when the microcontroller is

giving pulses with particular frequency to ULN2003, the

motor is rotated in clockwise or anticlockwise.

Fig. 1 Interfacing Stepper Motor to Microcontroller

Interfacing Stepper Motor with 8051

We now want to control a stepper motor in 8051

Primer Board. It works by turning ON & OFF a four

I/O port lines generating at a particular frequency.

The 8051 Primer board has four numbers of I/O portlines, connected with I/O Port lines (P0.0 P0.3) to

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rotate the stepper motor. ULN2003 is used as a

driver for port I/O lines, drivers output connected

to stepper motor, connector provided for external

power supply if needed

Source Code

#include

#include

void DelayMs(unsigned int);void Clockwise (void)

{ unsigned int i;

for (i=0;i