Added link to enhanced firmware info page

Author: sheabunge

Diff for: README.md

@@ -4,7 +4,7 @@ Ever wanted to protect your NXT from a pesky brother or sister?
 
 When you startup your NXT, instead of showing the startup animation, it will prompt for a four digit code. The code must be entered correctly before you can access your NXT. If you enter the wrong code, the NXT will flash a message, otherwise, the program will end, allowing you to access your NXT. The dark grey button will turn off the NXT instead of ending the program.
 
-If you use the NXC Enhanced Firmware, the dark grey exit button will not simple exit the program, instead it will turn off the NXT. LockCode *can* be used without the enhanced firmware, but this functionality will be disabled, decreasing the usefulness of this program.
+If you use the [enhanced NBC/NXC firmware](http://bricxcc.sourceforge.net/firmware.html), the dark grey exit button will not simple exit the program, instead it will turn off the NXT. LockCode *can* be used without the enhanced firmware, but this functionality will be disabled, decreasing the usefulness of this program.
 
 The first time the program is run it will ask you to set a code. If you forget the code and want to set a new one, simply delete the file `LockCode.dat` from the NXT using something like [NeXT Explorer](http://bricxcc.sourceforge.net/utilities.html) or [NeXT Commander](http://nextcommander.sourceforge.net/).
 There is also a program included, [`Delete Code.nxc`](https://github.com/bungeshea/LockCode/blob/master/DeleteCode.nxc), that will do the same.