PWM out ports confused

Hello. I am from a rookie team, and we are having trouble with our digital sidecar. Our PWM out puts are mixed up- on the program (we are using the labview default) it says it is connected to port 2, but really it is connected to port 3. Also, when it says it is connected to port 4 it is connected to port 1. Does anyone know how we might figure out which port is which aside from simply testing every output, and does anyone know what’s going on with our sidecar? thanks for your time

Check this document and see if your DB37 cable is broken, I have a seeking suspicion that it is.

Does your robot signal light blink? If not, your DB37 cable is broken.

It really must suck for rookie teams when problems like the ribbon cable crop up - you just don’t expect something like that to be wrong, and just assume you’re doing something wrong. A veteran team, on the other hand, would likely know that the code is correct, and start swapping out components with spares from previous years, eventually discovering the cable is bad, and then hopefully finding the document on how to fix it.

FWIW, our cable was bad as well, and it really is rather easy to fix. The instructions FIRST posted are great!

We were helping out a Rookie team at the Stl Science Center on Sunday and they were having a problem with their RSL light/RSL indicator on the Sidecar, neither would flash. The first indication to me was the Ribbon cable issue. They were using the new Ribbon cable but had not fixed it, as they didn’t hear about this issue. We swapped our DB37 cable with theirs and the RSL came on immediately. It is interesting though because their drive was working* (although I don’t know for sure if their PWM channels were flipped as well) but after the cable swap their drive was working normally. Interesting failure mode for the Ribbon cable.

To anyone reading this topic: Please remind all other teams you know to read the Team Updates. This info was covered, but not every team (especially rookies) know that there are updates. This is a great reach-out that can be a starter for team-team help and communication in your region.

We (as a rookie team) ran into the cable issues (not sure that is your problem, but could be). We had flipped 1 end (to fix the KOP packing mistake which is mentioned in the Team Updates), but hadn’t managed to press the connection all the way on. As a result, the pwms never seemed to output anything.

Key thing to look for is the little led next to the “RSL” connector. If the cable is working, it should flash continuously once the cRIO is started up.

Thanks a lot guys. The ribbon cable was our problem, as we found out after testing three different sidecars. I have read all the team updates, but apparently didn’t pay enough attention to the small paragraph about the ribbon cable. Not being familiar with part numbers, the phrase “DB87” didn’t remind me of the ribbon cable.