Vex 2.0 VexNet problems URGENT

My team is having problems using the new vexnet keys we cant get it to connect to the robot via wireless connection

if this is any help we use robotC

please hurry we have a competition this weekend

Please give some more background.

Have you updated the master firmware on cortex and joystick to 4.0?

Does tethering with the USB A-A cable from cortex to joystick work?

Do VEXnet 1.0 keys work?

Which version of ROBOTC?

Was this working before or did you just receive the new VEXnet 2.0 keys?

Did you update to the new firmware?

The new keys need to new firmware to function.

You can get it here: (step 2)

this gives you the new firmware upgrade software which you can then use to upgrade the cortex and joystick.

Keep in mind that when you update the firmware, you will have to re-download you code and recalibrate your joystick.

Hope this helps.

thanks but we just tried the old ones again and it started working is it legal to use the old usb s

It is legal to use the old VexNET keys but the new ones will work if you upgrade your firmware as described in the other posts. The reason is that the old firmware only works with the old keys while the new firmware works with both types of keys.

We still have problems with our program after we have updated the firmware. Please help me as soon as you can. Thanks.

Do the old keys still work?

Our vexnet keys still work plz tell us if there are any other problems that we could try to fix.

I assume you’re talking about the first generation VEXNet keys. Max-D already asked this, but can you confirm you’ve updated firmware to version 4.0? I don’t know if ROBOTC is shipping with firmware version 4.0 Use this link to download the 4.0 firmware updater. The firmware update box should say “CORTEX_4_01.bin” at the bottom of the window. Make sure to update both the Joystick and the Cortex Microcontroller.

Telling us what the lights are doing when you try to connect might give us a clue.

Does the light on the new keys flash once when you first turn it on?

Once we have updated the cortex to 4.0 firmware, the lights are giving us false signals. We get red light on the robot even when the main battery, backup battery and the power expander battery were all new and fully charged

Red lights on which LED’s? All three?

You updated the joystick firmware too to the new one in the utility too?

We re-flashed the robot C firmware too thinking it was necessary but it may not be. I was not sure if they are completely independent. We re-paired the joystick to the cortex too to be safe.

Outside of no debug stream we have been happy and have not had Vexnet drop outs with the new keys (but we are the only ones running them so I go back to the first guy on the street with a cable modem analogy)

Make sure you do this; the joystick one needs to be done too!

They’re completely independent; it’s not necessary.

Not sure about this but whenever you have issues w/ VexNET the first thing you should try is re-pairing.

The robot is working… We have updated the joystick plus the cortex both. The robot is working fine it is just that robot led on the joystick which is giving false data. It happens with both vexnet 1.0 & 2.0

What is the false data?

The backup battery status is now disabled when in driver and auton modes but I doubt that’s what you mean.

Not the backup battery. Even when we have fresh batteries the robot light shows red. Even the online window shows battery voltage at 8.1. It just doesn’t make sense.

How old is your power expander? Do you have it plugged into the Cortex to get battery status from the expander? I can’t remember the details but monitoring an old expander with the Cortex didn’t seem to work for us and gave some weird behavior. If you have a cable from the expander to the Cortex to monitor the expander voltage, try unplugging that cable and seeing if the situation improves.

So little data to go on what might be the issue.

Cheers Kb

I will let you know how it goes. Our power expander is from last year and i am sorry but i don’t remember if i get power expander’s battery voltage. We used the same power expander. The issue started as soon as the firmware was updated