Thread: Problems with updating speed on the actual field
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Unread 20-03-2013, 10:04
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Re: Problems with updating speed on the actual field
Could be a CPU issue - if the image-analysis task is taking too many CPU cycles, it could starve the PID or at least make the PID unpredictable.

Could be a starvation issue: We had a bug once where we had a tight sensor-checking loop on one thread that never yielded, which caused the robot to be undriveable. But when we put a printf in, things worked - this is because internally, the printf call yields execution to other threads. The correct solution was to put a short wait() statement in so that other threads could get a turn on the CPU. Your camera code could be similar - if there's never a wait() call in it, then it could completely monopolize the CPU.