A I2C controlled, LCD enabled Thermometer: Unterschied zwischen den Versionen

Version vom 3. November 2009, 02:08 Uhr

Here's a demonstration of a very tiny Arduino project: It's a microcontroller driven very precise digital thermometer.

1 Ingredients =

• Arduino Mini Pro
• JHD 162A LCD display
• SE95 I2C temperature sensor on a board from Horter & Kalb http://www.horter.de/i2c/index.htm
• 25 kiloOhm Poti
• 1 kiloOhm Poti
• Breadboard
• 3x AA Alkaline cell

Costs:

• Arduino Mini Pro 15€
• JHD 162A LCD display 10€
• SE95 I2C temperature sensor & board 5€
• 25 kiloOhm Poti 0.25 €
• 1 kiloOhm Poti 0.25 €
• Breadboard + jumper cables 10 €
• 3x AA Alkaline cell 2 €

Overall costs: 42.50€

Surely not a very competitive price. But the brain value was immense!

2 Program

Here's the sketch:

#include <Wire.h>

#define tmpaddress 0x48

void setup()
{
  Wire.begin();
  Serial.begin(1200);
}

void loop()
{
  // get the temperature
  Wire.beginTransmission(tmpaddress);
  Wire.send(0x00);
  Wire.requestFrom(tmpaddress, 1);
  int temperature = 0;
  if (Wire.available()) {
    temperature = Wire.receive();
  }
  Wire.endTransmission();

  Serial.println("-----------");
  Serial.println(temperature-3);
  delay(1000);
}

3 Tests

• battery voltage: 4,79 V
• current: 17 mA
• power consumption: 81 mW

4 Images