2006 CMUcam2 Code

[nheft]

I tried holding the reset button while powering up. Still getting random code errors.

I sprinkled some printf's into Process_Data_From_Master_uP - one at the beginning of the module, one to print out the entire rxdata buffer, and one at the end of the module. When the code error occurs I am observing that Process_Data_From_Master_uP executes one time.

When the mis-aligned rx buffer problem occurs, it looks like it's happening from the second message on; the first rxbuffer received after initialization looks OK.

I also tried a simple delay loop before IFI_Initialization to give the oscillator a few tenths of a second to stabilize before trying to do anything. This did not help either.

Another programmer from Team 358 loaded frc_camera_s on his RC and could not find a problem. I tend to believe there is a marginal timing problem somewhere that just doesn't occur with all RC's and does not occur with IFI default code.

For now, my work-around is going to be: (1) if the LED's show a code error, cycle power and (2) if the packets get misaligned, trap on a lack of proper incrementation of packet_num and force a code error via an infinite loop, taking us back to step 1. This trap can be disabled after five consecutive good packets since the RC seems to behave OK once it gets off to a good start.

Originally Posted by Kevin Watson

I think we can go on the assumption that it's not caused by the camera code directly. The only thing that immediately comes to mind is some kind of race condition where the processor comes out of reset before the oscillator is stabilized. If I get a chance, I'll call IFI today and see what can be done about this. As an experiment, you might try holding the processor in a reset state while powering up. Do it enough times to get real statistics.

-Kevin