Short version of question: I bought one of these: http://imall.iteadstudio.com/im120606013.html and am trying to figure out how to get it going with the Raspi. I have some assumptions about how it should be connected, but I am not 100% sure, and I'm looking for confirmation.
There are three power pins: VIN, GND, and +5V. I think VIN should be connected to the positive terminal of my 12V battery, the +5V should be connected to a +5V pin on the Raspi, and the GND should be connected to both a GND on the Raspi and the negative battery terminal. Is that correct?
There are four input pins: IN1-4. I believe these can be connected straight to any GPIO pin. Then above those there are four pins, an ENA, +5V, +5V, ENB. There is a jumper between each EN and one of the +5Vs there.
Then the four output pins on the side would go to the two terminals of both motors.
Is this all correct?
The longer version of the question: I am going through the O'Reilly book Make A Raspberry Pi Controlled Robot. Googling for that, rather shockingly I could not find any forum threads where people were trying to follow the instructions in the book and discussing them. Frankly I think the book is a bit vague in places. I know some about electronics but am by no means a guru.
The book actually recommended getting this for the motor controller: https://www.sparkfun.com/products/9670 I think that what I bought is about the same as this (much cheaper) but I am not fully sure. I would have purchased that, but it was out of stock when I ordered what I did, so I had to search elsewhere. I am thinking it might contain extra protection circuitry but it is not clear how I would modify my own connections to use the one I bought rather than this.