Motor Port Problems


I’m having issues with one of the motor ports in my robot. When I connect a motor in port 5, it seems as if its not giving any current, is there any way to fix this?

Also, when trying to connect the microcontroller to the joystick with vexnet keys, sometimes it takes a lot of time before it connects, and when it does it tends to lose connection. The leds in the joystick and micro start flashing red, but I don’t think it has to do with the vexnet keys because they are new. I have been told that it might have to do with the main battery port. Any thoughts?

There are many things it could be. Have you tried swapping out motor controller 29 and the motor itself? I assume you probably have. A likely possibility is code, if you post it someone can check it for you. Otherwise the cortex could be broken but this is unlikely, how old is it?

What often happens with the battery connections is they get loose after lots of use. This could be on the cortex connector or on the battery connector, see if the contacts are loose, or if the cortex ones have splayed open too far. If the cortex loses power for a split second then vexnet will lose connection (a backup battery is designed to prevent this), so this may be the problem.
If you describe exactly what lights you are seeing it might also help to determine the problem.
It is not unheard of for new vexnet keys to be faulty so the best thing to try is swapping each one out in turn for one you know works (borrow another team’s if necessary).
Basically the more information you can give, the better.

I have tried to connect the motor directly to the cortex but nothing happens. I’ve had the cortex for less than a year. And i am currently not using a code in that cortex, I have been trying it out with the online window of easy C.

When trying to connect the first few seconds, the Joystick flashes as if its connected but the cortex lights turn red only for a split second and the joystick looses connection, and if left turn on to see if it connects again, the vexnet led (second light in cortex, third light in joystick) start flashing red on both. If the contacts are loose, what should i use to fix it?

I almost forgot to say that when I connect the motor without the motor controller 29 the motor works, but when I use it, it does nothing, it works on other ports, but not in port 5 :confused:

Not a good idea to connect a 2 wire motor to any 3 wire port on the cortex, I have seen ports stop working before and at least some of these can be attributed to students plugging in a motor without the MC29 (the school team I mentor actually has a cortex with the same problem on port 9 I will be looking at over the christmas break).

This sounds like a vexnet key problem. If it was the battery connections I think the joystick lights would be just as you describe but the cortex would go back to the flashing orange “searching” pattern - because its essentially powering on from the beginning again. From what you describe, the cortex hasn’t lost power but is registering that it can’t get a vexnet signal.

Can I use a “Y” extention as a remedy to my problem? Since the current that the port gives will be divided in two, will this affect the speed of two 269 motors???

Use motor controllers on both motors after the splitter.