Trouble compiling code for Arduino Mega/ESP8266 wifi shield and Blynk App

[PeteKnight]

@titi I’d suggest that you start by reading this:

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…

and if you are still having problems I’d suggest that you create a new “Need help with my project” topic and provide ALL of the information that is requested when you create the topic, along with full details of how you have connected your two boards together, and whether or not you have ever uploaded a sketch to the ESP-01.

Pete.