Serial Data on TX Pin

I have the blank sketch below that sets the baud rate for the serial port. With a scope on my Uno TX pin 1 I capture a trace from the print and the serial monitor displays "Ready". All good and expected so far.

My question is when I send data from the serial monitor I would expect a trace and data to show up on the RX pin 0 but I never see it. Any idea what I'm missing? Do I need a sketch to echo the RX data to TX?

void setup()
{
  Serial.begin(9600);
  Serial.println("Ready");
}


void loop()
{
}

Does the RX LED flash when you send data to the Arduino?

No it doesn't.

Then the device that is sending data is not connected to the same port that the Arduino is. The Arduino is not getting data.

Spot on. I found a wiring problem.

So its still not working as expected. This round I have a completely blank sketch running and the serial monitor up at 9600 baud. I connected pins 1 and 0 (tx to rx). When I send data via the monitor both the RX and TX LEDs on the Uno light up but the monitor window doesn't show any data. I tried all other baud rates without luck. I would have expected to see data echoed on the monitor.

Try shorting TX and RX on arduino and try viewing in the Serial monitor.

void setup()
{
  Serial.begin(9600);
  Serial.println("Ready");
  }

String str=" ";
void loop()
{
  while(!Serial.available());
  Serial.print(Serial.read());
  delay(1000);
}

Do nothing until some serial data arrives. When that happens, read the print the data. When you've read all the data, stuff your head in the sand for one whole second. Then, go back to waiting for data.

I really can't see the point of getting sand up your nose.

I can't see the purpose of the useless String instance, either. Or the class, for that matter.

I like sand between my toes not up my nose. So an echo has to be in the loop.