[FTC]: Playing Forensic Roboticist.

[PhilBot]

Two ideas gelled for me today, and made me go Hmmmmm.

After a bunch of perfect test auto runs, I had my File Error occur on two runs in a row. It occured to me that I hadn't powered down the NXT for a while, so I did, and things started working again.

It's amazing how we assume that computers "just run" these days, because it took me this long to suddenly think "memory leak".

All of a sudden I wondered if there is a memory leak in the labview NXT firmware, and perhaps these problems occur based on how long the NXT has been running, or how many times a certain type of operation is performed.

I did some more research on the "File Error" message and it seems like it may be related to 1) An invalid array index or 2) failure to allocate dynamic memory.

I could see how a memory leak could cause #2.

I also wonder if just sitting on the playing field, running the code template for 2-3 minutes could cause a memory leak to grow to the point where it shuts down the NXT program when you start really doing stuff.

On a related note, during FLL season, I casually used an FTC NXT in one of our FLL robots (that was programmed in NXT-G). This NXT had been upgraded to firmware version 1.12. After several instances of the NXT program just locking up while it was running, I went back to the "release" 1.05 firmware. Never had the lockups again.... Hmmmmm.

Does anyone know if there is a way to read the amount of "free memory" while running a program on the NXT.... it might be enlightening...

Phil.