Gravity: Analog Water Pressure Sensor (แท้จาก DFRobot)

/************************************************************
Water pressure sensor demo(Computer serial port)
- Obtain the water pressure through the output voltage
of the sensor.
**************************************************************/

/************************************************************
Water Sensor Key Parameter
- Parts No.:KY-3-5
- Sensing range: 0 - 1.6 MPa
- Input Voltage: 5VDC
- Output Voltage: 0.5 - 4.5 VDC
(Linearly corresponding to 0 - 1.6 MPa)
- Accuary: 0.5% - 1% FS
**************************************************************/

/************************************************************
Water Sensor Calibration

The output voltage offset of the sensor is 0.5V (norminal).
However, due to the zero-drifting of the internal circuit, the
no-load output voltage is not exactly 0.5V. Calibration needs to
be carried out as follow.

Calibration: connect the 3 pin wire to the Arduio UNO (VCC, GND and Signal)
without connecting the sensor to the water pipe and run the program
for once. Mark down the LOWEST voltage value through the serial
monitor and revise the "OffSet" value to complete the calibration.

After the calibration the sensor is ready for measuring!
**************************************************************/

const float OffSet = 0.483 ;

float V, P;

void setup()
{
Serial.begin(9600); // open serial port, set the baud rate to 9600 bps
Serial.println("/** Water pressure sensor demo **/");
}
void loop()
{
//Connect sensor to Analog 0
V = analogRead(0) * 5.00 / 1024; //Sensor output voltage
P = (V - OffSet) * 400; //Calculate water pressure

Serial.print("Voltage:");
Serial.print(V, 3);
Serial.println("V");

Serial.print(" Pressure:");
Serial.print(P, 1);
Serial.println(" KPa");
Serial.println();

delay(500);
}

/************************************************************
Water pressure sensor demoB(LCD1602)
- Obtain the water pressure through the output voltage
of the sensor.
**************************************************************/

/************************************************************
Water Sensor Key Parameter
- Parts No.:KY-3-5
- Sensing range: 0 - 1.6 MPa
- Input Voltage: 5VDC
- Output Voltage: 0.5 - 4.5 VDC
(Linearly corresponding to 0 - 1.6 MPa)
- Accuary: 0.5% - 1% FS
**************************************************************/

/************************************************************
Water Sensor Calibration

The output voltage offset of the sensor is 0.5V (norminal).
However, due to the zero-drifting of the internal circuit, the
no-load output voltage is not exactly 0.5V. Calibration needs to
be carried out as follow.

Calibration: connect the 3 pin wire to the Arduio UNO (VCC, GND and Signal)
without connecting the sensor to the water pipe and run the program
for once. Mark down the LOWEST voltage value through the serial
monitor and revise the "OffSet" value to complete the calibration.

After the calibration the sensor is ready for measuring!
**************************************************************/

#include 
#include //LCD header file
const float OffSet = 0.483 ;
float V;
int P;
unsigned int lcd_r = 0, lcd_g = 0, lcd_b = 0;
unsigned long delaytime = 0, lighttime = 0;

DFRobot_RGBLCD lcd(16, 2);
void setup()
{lcd.init();
delay(5000);
Serial.begin(115200);
Serial.println("hello start");
lighttime = millis();
lcd.setCursor(0, 0);
lcd.print("Water Pressure:");
lcd.setRGB(255, 255, 000);
}
void loop() {
lcd_r = random(256);
delayMicroseconds(10);
lcd_g = random(256);
delayMicroseconds(10);
lcd_b = random(256);
if (millis() - lighttime > 3000)
{
lcd.setRGB(lcd_r, lcd_g, lcd_b);
lighttime = millis();
}
//delay(100);

V = analogRead(0)* 5.00 / 1024; //Sensor output voltage
P = (V - OffSet) * 400*10; //Calculate water pressure
lcd.setCursor(3, 1);

lcd.print( P/ 10000% 10); //LCD display
lcd.print( P/ 1000% 10);
lcd.print( P/ 100 % 10);
lcd.print( P/ 10 % 10);
lcd.print('.');
lcd.print( P % 10);
lcd.print(" kPa");

}