The 8.2 (or 8.3) Battery Voltage Bug

[Keith Watson]

Originally Posted by eugenebrooks

...Either the compiler is not correctly initializing the static variables that are not explicitly initialized, or the memory movement that might be caused by the variable landing in a different segment, the one with explicit inits, caused a memory stomping problem to go away.

The compiler creates a section of code in the binary where all of the static initializers are called. I have always assumed any sort of processor reset would call this block of code before calling main().

Originally Posted by gobeavs

That bug hit us once and disabled us for a round at PNW, but we have found a way to avoid it. When we turn our robot on at the beginning of the round we have someone at the OI looking at the battery voltage to give us a thumbs up or down depending on whether it is showing ~12 or 8.2. If we get 8.2 we just power cycle (not just reset, because that screws up the camera). It saved us at least once later on.

We encountered behavior where the symptom is that the static initializers are not being called by a reset under certain conditions. See the recent thread Camera does not search in autonomous mode after reset for a full description of those conditions.