In my original code, I have a delay at line 80. https://www.hackster.io/helge-johnsen/facebook-fan...I can't see it in your code. So I'm not sure where the 15 seconds delay comes from.
Or did I missunderstand your quiestion? The 15 seconds from startup to the first number displays. It takes some time for the board to connect to wifi and then to Facebook.
To be honest, I have never received the ERR1 message myself. The reason for ERR1 is that fancount is not greater than 0. That is, it is 0 or less. It may also be that fancount is not a number. A little bad code, because this should have been checked in advance.Try a Serial.println(fancount); Between lines 69 and 70. Is there a number or something else?I have never renewed my access token. My display has run without errors since May. There may be a problem with your Facebook APP or settings.
Depending on what type of board you have you should select the board that fits in Arduion IDE. There are several types and you might have to download a libary for your type of board.Depending what works for your board you can define the pins in different way. Try some of the examples from the display libary to check if it works: https://github.com/bremme/arduino-tm1637/tree/master/examples
It looks similar and it will probably work. What you have to check is the VCC and if it's capable to drive the display directly from the NodeMCU-board. Otherwise you have to power the display in another way.
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