C Programming and Raspberry Pi Help! 1. I have the Raspberry Pi 2 Model B 2. I h

Question

C Programming and Raspberry Pi Help!

1. I have the Raspberry Pi 2 Model B

2. I have breadboard and resistor and the DS18B20 temperature sensor (3 pins)

3. I have jumper wires.

If you can help me with pictures of the wiring of the temperature sensor and also write a C code (NOT C++) on the raspberry pi that will display the temperature that'd be greatly appreciated!

I just can't figure out the wiring. I don't have a cobbler and I just need the exact pins so diagrams would be helpful and actual pictures!

Here's a pic of my sensor and breadboard:

Explanation / Answer

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# External module imports
import RPi.GPIO as GPIO
import time

# Pin Definitons:
pwmPin = 18 # Broadcom pin 18 (P1 pin 12)
ledPin = 23 # Broadcom pin 23 (P1 pin 16)
butPin = 17 # Broadcom pin 17 (P1 pin 11)

dc = 95 # duty cycle (0-100) for PWM pin

# Pin Setup:
GPIO.setmode(GPIO.BCM) # Broadcom pin-numbering scheme
GPIO.setup(ledPin, GPIO.OUT) # LED pin set as output
GPIO.setup(pwmPin, GPIO.OUT) # PWM pin set as output
pwm = GPIO.PWM(pwmPin, 50) # Initialize PWM on pwmPin 100Hz frequency
GPIO.setup(butPin, GPIO.IN, pull_up_down=GPIO.PUD_UP) # Button pin set as input w/ pull-up

# Initial state for LEDs:
GPIO.output(ledPin, GPIO.LOW)
pwm.start(dc)

print("Here we go! Press CTRL+C to exit")
try:
while 1:
if GPIO.input(butPin): # button is released
pwm.ChangeDutyCycle(dc)
GPIO.output(ledPin, GPIO.LOW)
else: # button is pressed:
pwm.ChangeDutyCycle(100-dc)
GPIO.output(ledPin, GPIO.HIGH)
time.sleep(0.075)
GPIO.output(ledPin, GPIO.LOW)
time.sleep(0.075)
except KeyboardInterrupt: # If CTRL+C is pressed, exit cleanly:
pwm.stop() # stop PWM
GPIO.cleanup() # cleanup all GPIO

---------------

----------

#include <OneWire.h>
#include <DallasTemperature.h>

// Data wire is plugged into pin 3 on the Arduino
#define ONE_WIRE_BUS 3

// Setup a oneWire instance to communicate with any OneWire devices
OneWire oneWire(ONE_WIRE_BUS);

// Pass our oneWire reference to Dallas Temperature.
DallasTemperature sensors(&oneWire);

// Assign the unique addresses of your 1-Wire temp sensors.
// See the tutorial on how to obtain these addresses:
// http://www.hacktronics.com/Tutorials/arduino-1-wire-address-finder.html

DeviceAddress insideThermometer = { 0x28, 0x94, 0xE2, 0xDF, 0x02, 0x00, 0x00, 0xFE };
DeviceAddress outsideThermometer = { 0x28, 0x6B, 0xDF, 0xDF, 0x02, 0x00, 0x00, 0xC0 };
DeviceAddress dogHouseThermometer = { 0x28, 0x59, 0xBE, 0xDF, 0x02, 0x00, 0x00, 0x9F };

void setup(void)
{
// start serial port
Serial.begin(9600);
// Start up the library
sensors.begin();
// set the resolution to 10 bit (good enough?)
sensors.setResolution(insideThermometer, 10);
sensors.setResolution(outsideThermometer, 10);
sensors.setResolution(dogHouseThermometer, 10);
}

void printTemperature(DeviceAddress deviceAddress)
{
float tempC = sensors.getTempC(deviceAddress);
if (tempC == -127.00) {
    Serial.print("Error getting temperature");
} else {
    Serial.print("C: ");
    Serial.print(tempC);
    Serial.print(" F: ");
    Serial.print(DallasTemperature::toFahrenheit(tempC));
}
}

void loop(void)
{
delay(2000);
Serial.print("Getting temperatures... ");
sensors.requestTemperatures();
  
Serial.print("Inside temperature is: ");
printTemperature(insideThermometer);
Serial.print(" ");
Serial.print("Outside temperature is: ");
printTemperature(outsideThermometer);
Serial.print(" ");
Serial.print("Dog House temperature is: ");
printTemperature(dogHouseThermometer);
Serial.print(" ");
}

--------

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