2003's FRC Robot Controller

Technical Programming
1

Hi all, just a quick question…

Would the FRC controller from last year be programmable with C as opposed to PBasic, using the C18 Compiler and the IFI loader?

Any help would be appreciated!

Cheers!
Ahmed :slight_smile:

2

Ahmed,

Absolutely not. In the old controller, the processor that you (the programmer) has access to is a Parallax Basic Stamp whereas the new controller is a Microchip PIC18C micro.

Sorry…

3

Ah, I see, thanks a lot. :slight_smile:

4

I informed my teacher, here’s what he has to say…

We are setting up a test board to layout our control systems, and we were hoping to use it to get familiar with the C language at the same time. The fact that the older processor does not operate with PBasic leaves with the one option of using our EduRobot processor.

Aside from the fact that the EduRobot controller would not provide enough voltage to run the controls, our concerns are a) how are we supposed to learn C if we have not bought a radio controller (the EduRobot does not have a tether), and b) if we do have a radio controller, does this mean our old joystick controllers are obsolete?

cheers…

5

  1. Your old operator interface w/joysticks will work with your old controller. Therefore, they are not “obsolete” in that they will run a robot (just not the 2004 robot).

  2. Get creative… Forget about an RC and work on autonomous mode. You will learn C and will get familiar with the IFI code.

  3. Do a search on these forums. There have been numberous threads about cheap RC controls and alternatives to the RC controls.

6

Ahmed,
Check out this thread. Our team has created a way to use the old OI and joysticks with the new EDU robot controller. It may be of use to you. I’ve received reports of several teams using this method with great results.

7

There are many ways to do input and output from the EDU controller witout using a radio.

For input…

  • Attach a switch across the “SIG” and “BLK” pins for a digital input.
  • Attach the two ends of a 100 kiloohm potentiometer (varaible resistor) to the “+5V” and “BLK” pins for an analog input and attach the middle wire to the “SIG” pin.

Just pretend the potentiometers are each one axis of a joystick and the switches are joystick buttons. In fact, you could even BUILD a joystick out of two potentiometers and two pushbutton switches, though I have no idea why you’d ever want to do so. :slight_smile:

For output…

  • Use the handy printf() function provided by FIRST
  • Attach a 5-volt LED across a digital output. I’ve never tried it (I can’t get my hands on the controller until tomorrow, GRRR…), but from the documentation it looks like you’d connect the LED’s cathode (negative lead) to the “BLK” pin and the anode (positive lead) to the “SIG” pin. Please correct me if i’m wrong!!!
  • Make the TTL output port do something. Does anyone know how? If I ever figure it out I’ll let you know.

All this information and more can be found in InnovationFirst’s EDU-RC documentation. Use it!

~Aaron

8

Thanks a lot for the feedback, I really appreciate it…