FMS enabling sequence?

[Jared Russell]

Originally Posted by Thad House

There's also another 20+ ms delay caused by the wpilibs if you use anything but the sample robot template. Could end up being up to 40ms depending on how the fpga loops.

Please elaborate?

[Thad House]

Originally Posted by Jared Russell

Please elaborate?

In LV I know that it runs disabled for 1 extra loop after it receives an enabled packet. Then it will run auto on the next enabled packet.

Based on the last time I looked in the Java code, it will run auto init, then the next packet run auto periodic. So unless you are starting your sequence in auto init, it wont run motors until it gets a second enabled packet.

Note that the whole time this is happening, the fpga is enabled, so it will run 20ms with the values it last receives. This is why there are times the robot jumps between disabled and enabled.

[Jared Russell]

Originally Posted by Thad House

Based on the last time I looked in the Java code, it will run auto init, then the next packet run auto periodic. So unless you are starting your sequence in auto init, it wont run motors until it gets a second enabled packet.

I do not think this is currently the case in Java (for IterativeRobot at least). It does check for the new data flag (via nextPeriodReady()), but this flag is not cleared after calling autonomousInit(), so autonomousPeriodic() should be invoked on the first packet

[Thad House]

Originally Posted by Jared Russell

I do not think this is currently the case in Java (for IterativeRobot at least). It does check for the new data flag (via nextPeriodReady()), but this flag is not cleared after calling autonomousInit(), so autonomousPeriodic() should be invoked on the first packet

Ah. They might have changed that then.

However, LV still does do this, and runs disabled one last time, and still has to wait for another packet to be sent before actually enabling auto. so auto in LV will have a delay of one packet before actually running auto code.