Intermitten power failures

[Greg McKaskle]

Camera communication is over TCP, and both the reads and writes have timeouts of 0.5 or 1 second on LV. I can't say what they are on C++. This was my basis for saying that I didn't expect a large CPU spike with the camera wasn't plugged in or powered.

When I said slow errors, that is of course not very definitive. It is true that last year's system could choke a bit when a large stream of fast errors were being sent to the DS. I don't think those errors would be only camera, but if you had lots of other errors, the camera could contribute to make things even worse.

As for loops causing watchdog issues, it isn't the fact that it is a loop, but the time that the code takes to execute. If the code manipulates a solenoid, a common occurrence last year, they code would often have delays and would cause a watchdog each time it ran. Even worse, it would cause many teleop packets to be overwritten since the teleop handler would take far longer than 20ms to execute.

A printout was inserted deep into the libraries last year to help determine when short disables were occurring. It kept count of the user and system watchdog disables since boot. If these correspond with the robot "power failures", then indeed, the WD was disabling the robot due to a missed deadline. If not, then it was something else.

Greg McKaskle