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isUpperCase()

Analyse if a char is upper case (that is, a letter in upper case). Returns true if thisChar is upper case. isUpperCase(thisChar)
thisChar: variable. Allowed data types: char. true: if thisChar is upper case.

		
if (isUpperCase(myChar)) {  // tests if myChar is an upper case letter
  Serial.println("The character is upper case");
}
else {
  Serial.println("The character is not upper case");
}