Most people run afoul of the fact that the two file formats are entirely different.  The .rbt file on your computer that was created by the NXT-G software is the "source" to the program.  That is, it is the list of blocks, their settings, their position on the beams, how the data wires are connected and so forth.
 
When you compile and download, the software generates a file containing a set of computer hardware instructions that the computer on the NXT brick knows how to interpret.  The format of this file is not only completely different (and therefore unreadable by the NXT-G software), but you cannot recreate the original source file from the compiled file on the robot!
 
So you can copy a compiled file off the robot and then back on to the robot (or to another robot), but you cannot create a NXT-G program file from the compiled and downloaded file on the robot.  The process is only one-way.  This makes it very important that you keep backup copies of your NXT-G .rbt program files.
 
I hope this helps your understanding of how it all works.
 
Stuart Roll
 
----- Original Message -----
From: [log in to unmask] href="mailto:[log in to unmask]">Washington, Darwin
To: [log in to unmask] href="mailto:[log in to unmask]">[log in to unmask]
Sent: Monday, October 26, 2009 11:55 AM
Subject: [VADCFLL-L] Uploading NXT Programs

My team has been attempting to upload a program from the NXT controller to the PC using the specified procedure.  The resulting file is consistently unusable.  The system does not recognize the file.  When we select it, we get a basic error message.  Does anyone else have this problem or know what we are doing wrong?

 

Darwin Washington

Coach, Team 2470

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