Cursor position in the text area

I found this script and edited it. On current pressing of any key, a div appears to the left of the text area (gray colored div) at the caret position where the text is written.

I want the div to appear on Keypress of Enter next to the caret position every time ( get the caret position and show div next to it on enter press )

, and if any other key disappears, the div.

I am a bit confused about how the keypress is being used here in this code.

here: http://jsfiddle.net/eMwKd/30/