LCD blank after upload blynk coding

[PeteKnight]

Okay, well there are so many things wrong with this sketch it’s difficult to know where to begin.

Because you are using an Uno and have connected your ESP-01 to pins 0 and 1 rather than using SoftwareSerial to create a virtual serial port on different pins, I’ll start by pointing you in this direction…

Understanding hardware and software serial ports

I’m still seeing frequent posts, mostly from new members of the forum, who are confused about how to add WiFi or Bluetooth connectivity to devices like the Arduino Uno, Nano or Mega, or from people who are trying to use serial communication with some other type of peripheral. I thought I’d try to put together some guidance on how to do this properly. First things first though – if you’re using a device such as an Uno, Nano or Mega that doesn’t have built-in internet connectivity then you shoul…

Once you’ve fixed that issue you’ll then be able to use your hardware serial port for debugging, and will be able to understand what is happening when you attempt to connect to Blynk.

Then you need to clean-up your void loop…

Keep your void loop() clean

Pete.