Merge pull request #621 from per1234/fix-plotter-labels

Fix Serial Plotter sketches for compatibility with all IDE versions

Author: per1234

content/software/ide-v2/tutorials/ide-v2-serial-plotter/ide-v2-serial-plotter.md

@@ -54,10 +54,10 @@ void setup() {
 void loop() {
   potentiometer = analogRead(A1);
 
-  Serial.print("Variable 1:");
+  Serial.print("Variable_1:");
   Serial.print(potentiometer);
   Serial.print(",");
-  Serial.print("Variable 2:");
+  Serial.print("Variable_2:");
   Serial.println(static_variable);
 }
 ```
@@ -78,10 +78,10 @@ void setup() {
 void loop() {
   random_variable = random(0, 1000);
 
-  Serial.print("Variable 1:");
+  Serial.print("Variable_1:");
   Serial.print(random_variable);
   Serial.print(",");
-  Serial.print("Variable 2:");
+  Serial.print("Variable_2:");
   Serial.println(static_variable);
 }
 ```