Serial.println(char(67));  // => C
Serial.println(char(81));  // => Q
Serial.println(char('C')); // => C
Serial.println(char('Q')); // => Q
Serial.println(char("C")); // => c
Serial.println(char("Q")); // => c

char const* ptr = "Q";
char(ptr);

char(unsigned char(uintptr_t(ptr)))