I need a little help...

[Nate Smith]

Originally posted by Sachiel7
Hey everyone!
First season is creeping up and everyones getting ready, but our team is doing a little something special...
My New team is hosting a competition for us and the other local teams in our area (RIchmond, VA) using the Prototyping kit that FIRST supplies. Since we are using our own game design, we need to build a competition control box to operate the game.
I Have the pinouts for the Competition port concerning the Channel Switch and the Disable option, but there are still a few more thing I would like to know:
1. I know FIRST supplies power to the OI through this port at the competition, so how do you do this?

The pinout used by the power feed to the OI from the arena controller has not been documented. It may be worth trying to get from IFI, but no guarantees...

2. If you cant do this (or easily) then is it still possible to operate the oi with competition control while the oi is using the adapter?

If you basically extend the disable switch wires, then yes you can, channel selection gets a little tricky though...

3. The Channel Switch: I'm still a little confused about what exactly this does. If you jumped the pins for the channel selection on four bots at the same time, would they each select a different channel automatically? or is there another set of pins that feeds the channel value to the oi? In my reading of the OI manual, I beleive that if you jump the pins, it autoselects a channel that has a RC (Robot Controller) with the matching team number. so, you could use up to 4 bots simutainously (it only supports 4 different channels). What if 2 robots transmit their team # over the same channel?

The channel jumper on the competition port basically enables the channel switch. You then need to use the channel switch to set which of the 4 additional channels the OI will use. Your understanding of how the channel search is done is close, but slightly backward. The OI locks onto a channel when it is powered on, and then when the robot is powered on, it scans all 40 channels for an OI broadcasting the matching team number. If two robots transmit under the same channel, you will see intermittent loss of communication from both machines, as the default behavior for the RC if it recieves data on its locked channel with the wrong team number is to go into disabled mode, just as if it was recieving no data at all...