isAlpha()
Analyse if a char is alpha (that is a letter). Returns true if thisChar contains a letter.. isAlpha(thisChar)thisChar: variable. Allowed data types: char. true: if thisChar is alpha.
if (isAlpha(myChar)) { // tests if myChar is a letter
Serial.println("The character is a letter");
}
else {
Serial.println("The character is not a letter");
}