New SVP-324 Controller

Just noticed this on the new products page. Doesn’t seem to be in stock yet and I’m sure you’re still working on the documentation but it looks very promising. Really like the idea of the servo control, fairly high current motor drivers and the two step-down regulators being built-in. Removes the need for a lot of typical additional hardware. Having the auxiliary MCU dealing with quadrature encoders is also very handy. Will the two USARTs be available for use? Looking forward to ordering one in my next batch of components :slight_smile:

Link for those who haven’t seen it:
pololu.com/catalog/product/1325

Very nice! At work we were looking at the SV-328 for a potential fleet of small robots, but maybe we’ll wait and check these out.

Judging from the picture of the back silkscreen it looks like there are plans for a future ATMega1284 version as well, rock!

-Adam

Hello,

The SVP is not in stock, but you can still backorder it. The 2 UARTs are fully available to the user. The two on-board MCUs communicate via the SPI pins.

- Ryan

There’s still some work to be done on the documentation and some testing to be done on the library, but we’re shooting to have units in stock by the end of the week. We’ll be posting more information to the product page as it’s ready (for example, I just put up a labeled pin diagram).

- Ben

I’ve looked through all the information that I can find on this, but can’t find my sollution.
I was wondering how fast the auxiliary micro can process quadrature encoder inputs. I have a really high resolution encoder that I want to use, but want to make sure this thing can handle it. I assume it runs on interrupts, do you know how long the routine takes to run?

Hello.

I couldn’t find a spec., either, and the best guy to ask that will be out on vacation for a few more days. The SVP can definitely handle up to a few kHz, and beyond that, it starts depending on things like the amount of SPI traffic (another interrupt source). If your transitions between channel edges are more than 100 us apart, you should be fine. However, if your encoder output is in the tens or hundreds of kHz range or more (e.g. few hundred or more CPR on a many thousand RPM shaft), the SVP won’t be able to keep up since it is not using a hardware counter.

We’ll get a better specification up later this week.

- Jan

Thanks Jan.

That sounds like it should work, but might be cutting it close. I think I’ll try it out and hope that the Error check picks up any problems.
The correct info in the spec would be helpful to confirm for future use.

You mentioned that the SPI runs off interrupts. I expect this wouldn’t interfere with the counting very much would it? It may be a problem to lose too many counts as I’m building a balancing robot with this and it will need quite accurate speed feedback.

Steve