Voltage drops to 1v on digital pin. -UNO

I have a genuino UNO. Just learning how to use it. When I hook up the 5V source, It shows 5V. Then I plug in a resistor, and LED, i get 5 V between the source, and ground. Good. When I plug into any of the digital pins, I get 5V, until I put an LED, and resistor into the circuit. It drops to 1.6V. No Good. Any ideas? It's barely enough to light the LED. It's super dim.

(deleted)

This is what I have put into it for testing purposes.

void setup() {
// put your setup code here, to run once:
}

void loop() {
// put your main code here, to run repeatedly:
digitalWrite(2, HIGH);
digitalWrite(3, HIGH);
digitalWrite(4, HIGH);
digitalWrite(5, HIGH);
digitalWrite(6, HIGH);
digitalWrite(7, HIGH);
digitalWrite(8, HIGH);
digitalWrite(9, HIGH);
digitalWrite(10, HIGH);
digitalWrite(11, HIGH);
digitalWrite(12, HIGH);
digitalWrite(13, HIGH);
}

The only thing that your code does (in loop()) is enabling the internal pull-up resistor. Maybe add some pinMode statements in setup (as indicated by @spycatcher2)?

kronk:
I have a genuino UNO. Just learning how to use it. When I hook up the 5V source, It shows 5V.

To what do you hook it up? What shows 5V?

kronk:
When I plug into any of the digital pins, I get 5V

What do you plug in?

kronk:
until I put an LED, and resistor into the circuit. It drops to 1.6V. No Good.

How do you put a led and resistor in the circuit? Between Vcc and digital pin or between digital pin and GND.

(deleted)

Ok. I feel dumb. It was just that they weren’t set as outputs. And I went back, and figured out what was wrong with the code in my project too… Thanks for the help!