Switching the Channel for Competition

We are coming up on having our local Media Day and I only have a switch to change the channel on the 2003 Controller. Has anyone come up with a way to change the channel for local competitions without having to connect to the offical Competition port?

Thanks in advance

without the competition port adapter all the OI run on the same channel - using the comp port adapter IS the way to change channels - why would you want another way?

all you need is one jumper on a DB15 - what could be simpler than that?!

http://www.innovationfirst.com/FIRSTRobotics/pdfs/Competition_Port_Pinout_Guide.PDF

That is what I was looking for. It looks like the same from last year. I will have to check. Again thanks.

We have craploads of dongles for the competition port. If you’re referring to the UAH media day that we’ll be at … you’re more than welcome to borrow one. :smiley:

We wanted some blue LEDs flashing, so I jammed a paperclip in the right pins (I looked them up), played with the channal dipswitches, and got it set to 13. Now we have blue LEDs.

It’s not that hard, just don’t do anything dumb ;-).

For those of us too lazy to read the IFI paper … the pins to jam the paperclip into are 8 and 12.

I have also set the channel to 13 but we are still getting red leds. What could I be doing wrong.

I think you also have to set you team number to something other that zero?

Yea we have the team number set and everything is talking correctly. The only thing is the color led is red on whatever channel we set.

Where are the “sheets” for this kinda thing? I noticed the Chatsworth box had a LOT more stuff in it then mine does, and that kinda bugged me… I had been looking for like 30-60 mins for the pinout guide for the CPT port. Could someone please direct me twords the resources they used or other people used for their comp port things?

I think this is all the general public knows about the port:

pin 1 - VCC (note that IFI says that using this pin will void your warranty)
pin 5 - Autonomous Enable
pin 6 - Disable
pin 8 - Ground
pin 12 - Enable Channel Select

hahaha thats counting from the left or from the right whoops i guess it was the other way

Whats VCC?

is that a thing that would be used in the actual competitions?

Has someone fried their system yet using that port? :slight_smile:

They’re labeled on a standard 15 pin connector.

VCC is a direct connection to the OI power. You could use this pin to provide the operator interface with a power supply (connect a 9v battery to pins 1 and 8). You can also use this pin to get power from the operator interface (to power LCDs or the similar).

The reason IFI doesn’t want people messing with this pin is because it is a direct connection to voltage and could fry the OI if you’re not careful. That said, we’ve never ruined an OI – one time we shorted some of the wrong pins on the competition port and it started going crazy but a power cycle fixed that problem.

Alright, I think I’m up for building a dongle for our team. But since I’d rather not fork over $1200 for a new OI, I figured I’d ask and make sure my wiring scheme would work. It’s attached. (I’m sorry about the .bmp–my computer is a pain in the booty.)

Any tips for building one (other than to be careful and don’t short anything out)?

wiring.bmp (70.4 KB)


wiring.bmp (70.4 KB)

This is perfect. When I build them, I use a 3-position switch for the Disable and Autonomous function instead of using two switches. It will work fine with 2 switches though.

It’s really not difficult to make … and even if you do screw up, chances are you wont completely fry your OI. I’ve accidentally shorted the wrong pins a few times, and we’ve never lost an OI. We had one start acting weird … but a reboot fixed it right up.

Good luck. :smiley:

Real risky with the paper clip, We lost a OI CPU messing about with not up to specs wiring practices. Some of the pins on the Comp port go directly to the CPU in the OI and it clearly states that you fry things messing with the port and there is no warrenty. More than 150 dollars including the overnight shipping. As the Innovation First Service Tech said, triple check your wiring before stabbing on to the Comp port.

There is a doc on the Innovation First Web site that lists the pin outs. I’m having trouble getting to thier site right now so I will attach the PDF

Competition_Port_Pinout_Guide.pdf (5.95 KB)


Competition_Port_Pinout_Guide.pdf (5.95 KB)

Thanks for the input.

I noticed on my sketch that I just had 8 and 12 hooked together directly for channel access. IFI’s has a switch to enable/disable this. Is there any advantage either way?

And I’m just thinking out loud–if those are all the pins one needs to do autonomous and disabling and channel setting, how hard would it be to create a rudimentary arena controller? Just run the wires for four dongles to one central spot, perhaps add a timer to the disable circuit, and bada-bing! (I figure that even the channel -shouldn’t- matter, since the RC checks for team number as well. Of course, it wouldn’t hurt to give each robot their own channel in matches.)

Now for my final question: where on earth do you get those DB15 connectors? I checked my local Radio Shack, then their site. No luck either place.

<edit> And I’m just curious, since my team is always looking for easy sources of bling (is reminded of the team’s initial idea to stick strobe lights in the metal 2x4s)…is there enough power going through these pins to send juice to an LED (or similar device) indicate that said pins are connected? </edit>

Thanks again!