Hey there,
I'm currently trying to read out the sensor values of the DHT22 - which works very well with the serial monitor but not with the TFT display.
The TFT-display is - hopefully - correctly connected with the Arduino (as shown on the attached picture) but only gets white when powering it up. There is no chance to display the values or any written text.
Here the Example of the DHT22 readout:
#include "DHT.h"
#define DHTPIN 11
#define DHTTYPE DHT22 //DHT11, DHT21, DHT22
DHT dht(DHTPIN, DHTTYPE);
void setup()
{
Serial.begin(9600);
Serial.println("DHT22 Test START");
dht.begin();
}
void loop()
{
float h = dht.readHumidity(); //Luftfeuchte auslesen
float t = dht.readTemperature(); //Temperatur auslesen
// Prüfen ob eine gültige Zahl zurückgegeben wird. Wenn NaN (not a number) zurückgegeben wird, dann Fehler ausgeben.
if (isnan(t) || isnan(h))
{
Serial.println("DHT22 konnte nicht ausgelesen werden");
}
else
{
Serial.print("Luftfeuchte: ");
Serial.print(h);
Serial.print(" %\t");
Serial.print("Temperatur: ");
Serial.print(t);
Serial.println(" C");
}
}
I just tried to use the program "TFTDisplayText" written by Arduino in connection with the github-library but as I pointed out - the display only gets white.
/*
Arduino TFT text example
This example demonstrates how to draw text on the
TFT with an Arduino. The Arduino reads the value
of an analog sensor attached to pin A0, and writes
the value to the LCD screen, updating every
quarter second.
This example code is in the public domain
Created 15 April 2013 by Scott Fitzgerald
http://www.arduino.cc/en/Tutorial/TFTDisplayText
*/
#include <TFT.h> // Arduino LCD library
#include <SPI.h>
// pin definition for the Uno
#define cs 10
#define dc 9
#define rst 8
// pin definition for the Leonardo
// #define cs 7
// #define dc 0
// #define rst 1
// create an instance of the library
TFT TFTscreen = TFT(cs, dc, rst);
// char array to print to the screen
char sensorPrintout[4];
void setup() {
// Put this line at the beginning of every sketch that uses the GLCD:
TFTscreen.begin();
// clear the screen with a black background
TFTscreen.background(0, 0, 0);
// write the static text to the screen
// set the font color to white
TFTscreen.stroke(255, 255, 255);
// set the font size
TFTscreen.setTextSize(2);
// write the text to the top left corner of the screen
TFTscreen.text("Sensor Value :\n ", 0, 0);
// ste the font size very large for the loop
TFTscreen.setTextSize(5);
}
void loop() {
// Read the value of the sensor on A0
String sensorVal = String(analogRead(A0));
// convert the reading to a char array
sensorVal.toCharArray(sensorPrintout, 4);
// set the font color
TFTscreen.stroke(255, 255, 255);
// print the sensor value
TFTscreen.text(sensorPrintout, 0, 20);
// wait for a moment
delay(250);
// erase the text you just wrote
TFTscreen.stroke(0, 0, 0);
TFTscreen.text(sensorPrintout, 0, 20);
}
I searched the web like 4-5 hours but didn't get any hint. I think the problem is the port assignment but I don't know what is wrong.
Du you have an idea?
I would be very thankful for any hint.
