CAN issues

I’m the lead programmer of CyberGnomes Team 2013 we have hooked all of our electronics up ans when i opened the web based dashboard i could not see the pdp so i updated the roborio’s firmware and re-flashed it and when i did that all the CAN devices on the web based dashboard disappeared.

Galen Meesters
CyberGnomes Team 2013

Can we see a picture of your electrical?

You need to run the CTRE Phoenix Lifeboat to configure the roboRIO webdash for CAN.
CTRE Phoenix Framework Installer (.zip)

This separate step needs to be done whenever you reimage the roboRIO.

What’re the status lights on your talons doing? We had the same problem the other day, and all the talons were alternating flashing red slowly, meaning they couldn’t see the CAN. Turned out to be a bad talon, so once we found it we were good to go.

I used the lifeboat and now the talons and pcm are back but i still have not managed to get the pdp to show

we found a wiring issue in the CAN causing the pdp to not conect thank you for your help:)

Glad you found the issue!

A few lessons learned from our team, if anyone happens across it in the future:
–Check the LED colors on the devices - a bad CAN bus link will cause them to flash red. If there’s flashes of red, I wouldn’t expect anything to show up in the dashboard.

–Putting 6 brand new talon SRX’s on the CAN bus at the same time caused issues for us. They all assumed CANID 0. Not 100% sure what was going on, but presumably the 6x address collision was too much for the bus and the RIO to handle. We doubled back, put each one on one-by-one, programmed its address properly, and then the set of 6 would work.

Just to be 1000% sure of everything we pull all the fuses and check the CAN ID of each device, adding them one at a time. We never use zero for a device and we’ve adopted a high address number for non motor-control devices.

For wiring you can break the CANbus anywhere and you should see the termination (is it is installed) in either direction with a meter. If you can’t start checking for continuity from the middle to either end till you find the open. Also look for switching the plus and minus sides of the CANbus. We usually just do that visually (using green and yellow wires helps) That will cause nasty problems.