hi i am trying to build a 4wd rc toy car controlled by ps3. i am new to arduino and have no idea how to go about it. basically i have an uno and say, 2 dual motor controller and a usb shield.
understand that with 2 dual motor controller, i would have used up all my pwm pins on the uno so i cannot add on a servo to it.
where can i get the extra pwm pin for the servo or is there another arduino with more than 6 pwm pins that is compatible to the motor controller and usb shield?
4 motors only take 4 pins for PWM and that leaves you 2 for servo which only takes one each.
There's 15 pwm on the board you should be using for your USB shield
I'm pretty sure servos can be controlled from any I/O pin. They don't need to be used on PWM pins.
The h-bridge requires one PWM pin per motor as well as one digital pin (per motor) to control direction. I think there are still plenty of I/O pins left.
so far I have managed to source for the dfrobot code but not this tronixlab code. Are the codes the same?
Don't pay more than $4 for a L298N module. They're ubiquitous on ebay. The first one you linked to has the advantage of using an inverter on the direction pins is you can control direction with a single I/O pin. You can add your own inverter to the cheap L298N boards as save a lot of money.
Here's my L298N tutorial (I used a different microcontroller but the principles apply to the Arduino).
analogue pins can be used for digital I/O