ارتباط سریال در رزبری پای با زبان C

#include <stdio.h>
#include <string.h>
#include <errno.h>

#include <wiringPi.h>
#include <wiringSerial.h>

int main ()

{
int serial_port ;
char dat;
if ((serial_port = serialOpen ("/dev/ttyS0", 9600)) < 0) /* open serial port */
{
fprintf (stderr, "Unable to open serial device: %s\n", strerror (errno)) ;
return 1 ;
}


if (wiringPiSetup () == -1) /* initializes wiringPi setup */
{
fprintf (stdout, "Unable to start wiringPi: %s\n", strerror (errno)) ;
return 1 ;
}


while(1){

if(serialDataAvail (serial_port) )
{
dat = serialGetchar (serial_port);
/* receive character serially*/

printf ("%c", dat) ;
fflush (stdout) ;
serialPutchar(serial_port, dat);

/* transmit character serially on port */

}
}

}

🆔 @c_micro

مثال برای sprintf

#include <stdio.h>

int main ()
{
char buffer [50];

int n, a=5, b=3;

n=sprintf (buffer, "%d plus %d is %d", a, b, a+b);

printf ("[%s] is a string %d chars long\n",buffer,n);

return 0;
}


output:

[5 plus 3 is 8] is a string 13 chars long

❇️ @c_micro

❇️ مثال های کاربردی برای printf

#include <stdio.h>

int main()
{
printf ("Characters: %c %c \n", 'a', 65);

printf ("Decimals: %d %ld\n", 1977, 650000L);

printf ("Preceding with blanks: %10d \n", 1977);

printf ("Preceding with zeros: %010d \n", 1977);

printf ("Some different radices: %d %x %o %#x %#o \n", 100, 100, 100, 100, 100);

printf ("floats: %4.2f %+.0e %E \n", 3.1416, 3.1416, 3.1416);

printf ("Width trick: %*d \n", 5, 10);

printf ("%s \n", "A string");

return 0;
}

OUTPUT:

Characters: a A

Decimals: 1977 650000

Preceding with blanks: 1977

Preceding with zeros: 0000001977

Some different radices: 100 64 144 0x64 0144

floats: 3.14 +3e+000 3.141600E+000

Width trick: 10

A string

🔰 @c_micro

❇️ مثال های کاربردی برای scanf


#include <stdio.h>

int main ()
{
char str [80];
int i;

printf ("Enter your family name: ");

scanf ("%79s",str);

printf ("Enter your age: ");

scanf ("%d",&i);

printf ("Mr. %s , %d years old.\n",str,i);

printf ("Enter a hexadecimal number: ");

scanf ("%x",&i);

printf ("You have entered %#x (%d).\n",i,i);

return 0;
}

OUTPUT :

Enter your family name: Soulie

Enter your age: 29

Mr. Soulie , 29 years old.

Enter a hexadecimal number: ff

You have entered 0xff (255).

🔰 @C_micro

❇️ Calling a Function
💎 مثالی برا صدا زدن تابع

#include <stdio.h>

/* function declaration */

int max(int num1, int num2);

int main ()
{

/* local variable definition */

int a = 100;
int b = 200;
int ret;

/* calling a function to get max value */

ret = max(a, b);

printf( "Max value is : %d\n", ret );

return 0;
}

/* function returning the max between two numbers */

int max(int num1, int num2)
{

/* local variable declaration */

int result;

if (num1 > num2)

result = num1;
else

result = num2;

return result;
}

OUTPUT :

Max value is : 200


🔰 @C_micro

مثالی جهت آموزش pointers

#include <stdio.h>

int main ()
{
int var = 20;

int *ip;

ip = &var;

printf("Address of var variable: %x\n", &var );

printf("Address stored in ip variable: %x\n", ip );

printf("Value of *ip variable: %d\n", *ip );

return 0;

}

OUTPUT :

Address of var variable: bffd8b3c

Address stored in ip variable: bffd8b3c

Value of *ip variable: 20

🔰 @c_micro

کد اندازه گیری رطوبت خاک

#include <LiquidCrystal.h>

const int sensor_pin = A1;

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() {

lcd.begin(16, 2);

lcd.print("Soil Moisture");
}

void loop() {

float moisture_percentage;

int sensor_analog;

sensor_analog = analogRead(sensor_pin);

moisture_percentage = ( 100 - ( (sensor_analog/1023.00) * 100 ) );

lcd.setCursor(0, 1);

Serial.print("Moisture Percentage = ");

lcd.print(moisture_percentage);

delay(1000);
}

@c_micro