The Axon MCU with the VNH3SP30 :

I was wondering if there are any current existing
C libraries for us with the Axon MCU that can help
me control 4WD with the VH3SP30

Can someone also help me conceptualize how these
two devices would interface together? How to wire up
the four motors? How to program foward, reverse, left, right??


Welcome to our forum. I’m not familiar with the Axon MCU, and many others might not be, also. In general, if you have some product that is not from Pololu and want others to help you with it, you could at least link to it so that people who might be able to help don’t first have to go searching for your product.

If you’re talking about the Axon controller at society of robots, it looks like it’s just an AVR microcontroller, so you could start with looking at libraries for the AVR. It doesn’t take much to control the H-bridges; you just need two I/O lines for setting the direction plus a PWM output for setting the speed. I’m not familiar with the ATmega640, but that Axon page claims up to 9 PWM outputs, so you should have no problem getting four motor control channels set up. However, there’s a lot more to programming AVRs than figuring out wiring connections, so you should make sure you know what you’re doing before you get too invested.

- Jan

So is this digital I/O in the form of UART, or is it a general purpose
pin on the unregulated strips of i/o.

If the latter, then does the manipulation of the general pin
come down something like:

Pin A = Hi
Pin B = Low

Please bear with me, I am a newbie, but really enjoying
the learning aspect of it all.

A UART is for asynchronous serial communication, which has nothing to do with something like controlling a VNH3SP30 motor driver (though you could use the serial port to talk to something like one of our serial motor controllers). Your pin manipulation pseudo code is correct only in the most general sense; your actual C code for an AVR would look quite different.

I understand that you are new to this, and that’s why I warned you about the complexity of what you’re trying to get into. If you really enjoy learning this stuff, that’s great, but you’re really going to have to learn a lot more. You should read and make sure you understand the data sheet (which is hundreds of pages long), there are also many examples out there that you should study. For example, our Orangutans and 3pi robot use the same architecture, so you could look at the getting started information we have there.

- Jan