I have been working on an rc robot. I need help determinig what pins do what on the microcontroller. Can any one help?

I have found the pins for the two motors. Each motor has two pins. All of the pins for the motors respond when I make the motors go froward or backward. (by all I mean both pins for the motor that is mooving). I need to know which pin goes forward and which pin goes backward.

Picture of I have been working on an rc robot. I need help determinig what pins do what on the microcontroller. Can any one help?
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jeff-o7 years ago
Before you even try, do not connect the motors directly to the microcontroller.  It will die a painful death if you do that.

To find out what pins do what on a microcontroller, you need to look up its Datasheet.
TOCO (author)  jeff-o7 years ago
I mean likehere. figuring out the pins on the cotroller for the rc and then connecting those pins to an arduino.
jeff-o TOCO7 years ago
Oh, the pins on the Rumble Robot?  Well, according to the photo they are labeled 1.0 to 1.3.  Those four pins are connected to the arduino as shown in the schematic:

1.0 goes to pin 11 on the arduino
1.1 goes to pin 10 on the arduino
1.2 goes to pin 6 on the arduino
1.3 goes to pin 5 on the arduino

Is that what you're looking for?
TOCO (author)  jeff-o7 years ago
Sort of, I am using this car. I looked up the controller and it didnt show up anywhere. I simply used the rumble robot as an example. It was my inspiration for this project.
jeff-o TOCO7 years ago
Oh!  Well that's harder.  Do you want to connect the arduino to the car itself or to its controller?  Either way, you're going to have to open one of them up and see what's inside.
TOCO (author)  jeff-o7 years ago
I have already opened the car and that was my plan. I was planning to make something like the rumble robots but with an rc car with a dart gun built in.
jeff-o TOCO7 years ago
OK, good.  Are you able to post a picture of the circuit board, so we can help identify where things need to be connected?  Hopefully we'll get lucky and they'll use an off-the-shelf motor driver...
TOCO (author)  jeff-o7 years ago
I am so sorry, I had to hurry with the pictures because the battery was almost dead. I cant get it to charge well. Here are the pictures.
jeff-o TOCO7 years ago
Well, I *think* the blue board is the radio receiver, and those two clusters of transistors are the motor drivers.  Can you tell which board the antenna attaches to?
TOCO (author)  jeff-o7 years ago
The brown board had the antenna on it. I had to clip the antenna wire to get the car open. In other instructables they tap into a microcontroller on the cars like in the rumble robots. I dont know if it is the rectangle in the midle of the blue board or the circle "black blob" microcontroller in the lower right corner. I coultnt get a great pic of it. Maybe I could tap into the transistors. I dont know this is my first time playing around with a toy rc car. I normally play around with real rc car stuff. I have never made a robot b4 but I have made stuff with my arduino and some guts from and old rc car that became outmoded this year.
jeff-o TOCO7 years ago
Well, it's difficult to know what's under that blob, but can you read the part number printed on the rectangle in the middle?
TOCO (author)  jeff-o7 years ago
I googled it a week ago. Nothing showed up. I might have typed something wrong or typed the wrong thing. Here it is, EZ7T716. It also says 339.
jeff-o TOCO7 years ago
"339" is probably short for "LM339," a quad voltage comparator.  The other number is likely a lot number.  Unfortunately I'm not sure how it's being used in this case.  Do you have a multimeter that you can use to probe for voltages?
TOCO (author)  jeff-o7 years ago
I did that when I started the project with my grandfather who used to be an electrician. We were both confused with the results. I dont know if I was doing it right. This is my first project like this so I dont really know what to do at this point. After I get past this it is a piece of cake. Could you tell me how I would do that?
jeff-o TOCO7 years ago
Well, you'll need to trace the signals back from the motors to the controllers.  You can do that by turning off the power and using the "ohms" setting to find the place where the wires to the motors connect on the circuit board.  Note which component(s) are also connected.  Here's where some knowledge of electronics comes into play; when you trace a circuit to a component, you'll need to look up the datasheet for that component (assuming it isn't something simple like a diode, resistor or capacitor).  Then, determine which pin on that component is the "input" and continue tracing back until you've found a convenient place to hack in your own controller.

If you encounter a component or cluster of components that are arranged like an H-bridge, that's probably where you'll want to hook up your microcontroller.
TOCO (author)  jeff-o7 years ago
where would I connect the multimeter to the board or wires? what should show up on the multimeter?
jeff-o TOCO7 years ago
Well, you'd connect it anywhere there's metal.  If you're measuring resistance, a closed circuit (meaning the two points are connected) you should see zero ohms or something close (generally, anything less than 1 ohm).

This might be a fun afternoon for you and your grandfather! ;)
TOCO (author)  jeff-o7 years ago
We started this project a while ago and he is in mississippi right now. I am leaving for florida tomorrow so I cant work on the robot for a while.
TOCO (author)  jeff-o7 years ago
sorry its taking so long, I needed to get new batteries for my camera. I will charge them tonight and then post the pics tomorrow.
TOCO (author)  jeff-o7 years ago

I can post a picture later today
 

lemonie7 years ago
You've got straight DC motors which reverse with polarity?
Have you any type of controller for these, and what is it?

L