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sergioCorral842
28-01-2014, 18:26
We recently started having an issue where we would lose all communication with the robot over wifi. Downloading code over wifi works but when we start driving around or just have it enabled, the communication and robot code light will randomly shut off then come back on at random times for less than a second then shut off again.

The only way we can reconnect to it is to shut off the robot and restart. However, this is becoming an issue because it is starting to happen frequently. I have reconfigured the bridge and it fixed the issue for about an hour then it starts happening again.
Greg McKaskle
28-01-2014, 18:44
The charts tab may give more info on what is happening. Pay attention to the CPU usage, the lag and the packet loss.

By the way, for historical runs, go to the charts tab and launch the viewer. It is also in the Start menu.

Perhaps you want to post an image of the chart that shows the issues.

Greg McKaskle
Joe Ross
28-01-2014, 20:00
Are you in an area with a lot of wifi access points?
sergioCorral842
29-01-2014, 13:28
Are you in an area with a lot of wifi access points?

No, I am not. I am having a different issue now. The robot code light continuously blinks on and off. The communication light stays green.
Mark McLeod
29-01-2014, 13:49
That probably means either that your robot code is running too slowly somewhere and blocking execution, or conversely too fast and sucking up all the CPU.

As a first diagnostic look at your event log and pay particular attention to the CPU utilization line.
As a second diagnostic look at the Driver Station Diagnostics window for repeating error messages.
sergioCorral842
29-01-2014, 18:01
So I believe I might have figured out the issue. Since we are using 6 cims on our robot, when we go full speed, the amperage caused by the cims could be causing the radio to go bad. I am going to write some code that prevents the motors from instantly going to full power. Instead, it will accelerate to it. Will post back if it works.
Joe Ross
29-01-2014, 18:32
So I believe I might have figured out the issue. Since we are using 6 cims on our robot, when we go full speed, the amperage caused by the cims could be causing the radio to go bad. I am going to write some code that prevents the motors from instantly going to full power. Instead, it will accelerate to it. Will post back if it works.

If you have the radio wired properly, it should not be caused by current draw. However, if you have your radio placed near your CIM motors, you could see an issue.
sergioCorral842
29-01-2014, 18:45
If you have the radio wired properly, it should not be caused by current draw. However, if you have your radio placed near your CIM motors, you could see an issue.

I just tested driving on blocks with the radio on the outside of the robot (Completely away from the Cims). After about 25 seconds of driving the robot code light started flashing on and off and then I could not connect anymore.
Alan Anderson
30-01-2014, 12:12
The easiest thing to check right now is the power wiring to your D-Link. Make sure it's done as follows:

dedicated 12v output on Power Distribution Board (white Wago plug)
to
red and black wires on 12v-to-5v converter module

yellow and black wires on 12v-to-5v converter module
to
D-Link 5v power input

Any other wiring scheme will potentially cause the D-Link to lose power when the battery voltage sags.