task, implement code to 
	process the Backspace key to delete text characters in the buffer. 	
</pre>
</td>
</tr>
</table>
<p>You can copy this example program from the help page and paste it into the 
  source code editor.</p>
<h3> Hardware Interrupts</h3>
<p>Hardware Interrupts are short code fragments that provide useful services that 
  can be triggered by items of hardware. When a printer runs out of paper, it 
  sends a signal to the CPU. The CPU interrupts normal processing and processes 
