title: How to use an Arduino Uno as an FTDI programmer?
body: <p>Good evening, I've got an <strong>Arduino Uno</strong> board and I recently wanted to purchase an <strong>Ethernet Shield</strong> extension, in order to set up a small webserver. Unfortunately I ordered the wrong item and got a seperate <strong>Arduino Ethernet</strong> board now, which can't be programmed as easily as an Arduino Uno board and needs to be used seperately.</p>
  <p>As you can see in the image below, I can't unplug/remove the atmega from my Uno board as shown in some tutorials on the internet and thus I wasn't able to use it as an ISP yet.</p>
  <p>My question is can I use this Arduino Uno (R3 revision) board to program the Ethernet one without having to spend additional money on sort of an FTDI programmer (or programmer cable)?</p>
  <p>I attempted to connect the <strong>RX</strong>, <strong>TX</strong>, <strong>GND</strong> and <strong>5V</strong> pins of the boards since those are apparently programmed via RX/TX anyway, but that attempt failed paltry.</p>
  <p>Maybe someone can help me out.</p>
  <p><strong>Current setup:</strong></p>
  <p><img src="https://i.stack.imgur.com/8gTvCm.jpg" alt="Enter image description here" /></p>
  <p><em><strong>(Downscaled for web view, full size image <a href="https://i.stack.imgur.com/SeMJk.jpg" rel="nofollow noreferrer">here</a>)</strong></em></p>