PO Channels

[Joe Johnson]

Your robot and controller use Channel 40 if there is nothing plugged into the competition port.

If you plug in the official competition controller or if you have made a "yellow dongle" or the equivalent, you can get access to other channels.

Channel 40 is the dirtiest of all channels. I never recommend using this one if you have a choice.

The remaining channels you can use with the dongle and the switches on the front of the Operator Interface (OI) are:
Channel 4
Channel 13
Channel 22
Channel 31

Note that setting the channels is not something that is done at any time but only at set times.

The OI only sets its channels at wake up. Also, the Robot Controller (RC) only scans for new channels at reset time.

So... you have to set the OI switches, then reset the OI, then reset the RC, in that order.

Be sure that you reset the RC by turning off the robot or by hitting the reset button on the RC.

Obviously the "Robot Reset" button on the OI needs a valid radio link in order to function -- this is obvious but I have tried to reset the robot this way more times that I care to admit ;-)

Finally, as the RC scans for channels, it looks not only for a valid signal from an OI broadcasting on a particular channel, but it also looks for a valid signal with the same channel number as the one that the RC is set to.

This keeps someone from accidentally taking control of another team's robot.

Finally, I have spoken to Tony about the issue of other 900Mhz devices causing problems and he says that it is quite difficult to happen in practice. Basically, the IFI stuff is just under the legal maximums for signal strength. If the other device is also at this limit (not always the case but possible) it has to be CLOSER to your robot and ON THE SAME frequency band before it will cause any trouble at all. As a practical matter, they have not been able to cause any problems with cell phones.

Good luck.

Joe J.