VEX Robotics has released the following information on their website:
The VEX Robotics technical support team has identified an issue that some competition teams are experiencing in which the Cortex Microcontroller is unable to resume VEXnet link after a Microcontroller reset.
To help eliminate this issue at the VEX Robotics World Championship we are releasing a special version of the VEX Firmware, specifically for World Championship teams (3.21_Worlds). This firmware version modifies the Cortex re-initialization to help the VEXnet link reconnect in the event of a reset (i.e. caused by VEXnet Key “jostling”, power interruption, battery brownout, or static).
We know that competition teams dislike updating firmware so close to an event, so we are publishing this update in the hopes that teams will have a chance to test it “at home” before coming to VEX Worlds. If you’re comfortable with the new version, we strongly urge you to use it at the World Championship to help prevent potential problems related to a Cortex reset.
This firmware only updates a “back end” relinking protocol and it does not affect anything related to robot performance — you don’t need to tweak your autonomous mode, or anything like that.
Visit the VEX Forum thread on this firmware release for more discussions and to post any questions or concerns.
We recommend that all competition teams update to ROBOTC 3.08 and use the 3.21 Worlds firmware. The firmware can be downloaded using the VEXnet Firmware Upgrade Utility, or ROBOTC using the following procedures:
1) Connect the Cortex to the Computer over USB
2) Switch the ROBOTC Menu Level to Expert:
3) Go to Robot > Download Firmware > Master CPU Firmware > Choose File…
4) Navigate to VEXnet Firmware Upgrade folder in your Program Files directory and select “CORTEX_V3_21_Worlds.BIN”.
5) Press Open to open the firmware and begin the download process.
6) Once the CORTEX_V3_21_Worlds.BIN Master firmware has finished downloading, you should also download the ROBOTC firmware. Go to Robot > Download Firmware > Manually Update Firmware > ROBOTC Firmware > Standard File.