Selenium-IDE: How to simulate non-printable keys (ENTER, ESC, Backspace)?

Question

What is the exact HTML code to simulate ENTER, ESC, BACKSPACE and DOWN in Selenium IDE 1.3.0?

typeKeys didn't work nor did this:

<tr>
    <td>keyDown</td>
    <td>id=zc_0_4_3-real</td>
    <td>10</td>
</tr>
<tr>
    <td>keyUp</td>
    <td>id=zc_0_4_3-real</td>
    <td>10</td>
</tr>
<tr>
    <td>keyPress</td>
    <td>id=zc_0_4_3-real</td>
    <td>10</td>
</tr>

Answer 1

None of the solutions above helped me, however, the special keys described here this did the trick:

http://blog.reallysimplethoughts.com/2013/09/25/using-special-keys-in-selenium-ide-part-1/

sendKeys | id=search | ${KEY_ENTER}

Special keys - like normal keys, only a bit special. :)