lcd 20x4 i2c on NodeMcu
Posted: Fri Jun 14, 2019 5:03 amHello Guys,
i cant show anything on lcd by i2c. my conections: SCL -->D1 SDA -->D2 .
There is some data flow between nodemcu and lcd, i've checked it with osciloscope. nodemcu also can dim the backlight of lcd and turn it on again, so i think it works? but i can't achieve showing any text. also contrast was checked with multimeter if the potentiometer works. Have You some ideas what could have gone wrong?
i cant show anything on lcd by i2c. my conections: SCL -->D1 SDA -->D2 .
There is some data flow between nodemcu and lcd, i've checked it with osciloscope. nodemcu also can dim the backlight of lcd and turn it on again, so i think it works? but i can't achieve showing any text. also contrast was checked with multimeter if the potentiometer works. Have You some ideas what could have gone wrong?
Code: Select all
#include <LiquidCrystal_I2C.h>
#include <Wire.h>
LiquidCrystal_I2C lcd(0x27, 20, 4);
void setup() {
Serial.begin(115200);
//Use predefined PINS consts
Wire.begin();
lcd.begin();
lcd.noBacklight();
lcd.home();
delay(200);
lcd.print("Hello, NodeMCU");
lcd.backlight();
}
void loop() { // do nothing here
}