Hello All!
A few years ago someone wrote software for me. However, I recently started getting an error in the code when I tried to compile it.
Error: Compilation error: 'D7' was not declared in this scope.
Unfortunately, I can no longer reach the person who wrote the software. Does anyone know a solution?
#include <ESP8266WiFi.h>
#include <FirebaseArduino.h>In the IDE, on the menu bar, click on Edit then on Copy for Forum. Then paste you code here. It will be easier to read and copy
This double #include is pretty unusual.
D7 is part of Arduino language. So it should be defined.
Maybe some boards do not have it defined. What board did you select?
Is it the same board as you used earlier?
Thank you for your reply!
I use the ESP8266MOD and select in the IDE the "Generic ESP8266 Module"
My guess is that your code was written for another board...
I am not sure, but esp boards usually refer to pins as GPIO...
GPIO numbering doesn’t always match the labels on the board in an ESP. Specifically, D7 corresponds to GPIO13 as far as I remember
This is the picture of the board. D7 is on it. Strange.
Sure but these IO-pin names like "D7" are not really standard.
Look up this tutorial to find which real IO-pin number this is on ESP8266-based boards like the wemos D1 mini
If it is not yet defined you can define it yourself by
#define D7 13
I use ESPs for a lot of projects, and I am baffled as to why ALL of the board packages do not simply ALWAYS use the GPIO numbers silk-screened onto the boards. But the fact is, they don't. Sometimes it's the number screened onto the board, and sometimes it's the pin number on the little ESP module itself. Every time I use a new board, the first thing I do is verify the names of all GPIOs, as I've been bitten on the a** too many times by the illogical mapping.
arm?
a7
??
wrong thread?
No, but thanks for caring.
a7
My idea about the meaning of the three letters "arm" is an arm-based microcontroller
The picture shows definitly an ESP8266 D1 mini.
So what is the meaning of "arm" ?
I think he's asking for a clarification of this text. Probably sarcasm, or being silly, but then again, it's A7, so... (ducks, runs for cover). 
It's also the English word for that bit between your shoulder and your hand.
exactly the same three letters in german.
Still don't know what a7 means
Read the post above it.
Ok let's go on with a ping-pong game of short postings
which posting umber do you mean?
You should answer with a real hard riddle that creates a mimimum of 10 following up postings
Stern of the boat. Rear. Derrriere. The thing we don't dare mention.
mychars[]= {"btt"};
mychars2[]= {"gvdl"};
Serial.print("ah you mean");
for (byte i = 0; i< 3; i++) {
Serial.write(char(mychars[i]-1) );
}
Serial.println();
for (byte i = 0; i< 4; i++) {
Serial.write(char(mychars2[i]-1) );
}
Serial.println("! why are you afraid of clear writing?");