Alex W

Chris:

Did Netduino ever test this with a logic analyzer?

I'm back in the position of wanting to use this device with a N2P and was hoping to hear the good news that you fixed the I2C bug here.

You will need another power supply for sure.  The Netduino can only supply fairly low ma output, and large stepper drives use considerable quantities of power.

I'm not sure that the Netduino is a great device to use to pulse the stepper.  You need to have good realtime behavior for that, and the Netduino's strong point isn't realtime.  However there are step/dir driver modules that can be inserted between your Netduino and the stepper driver to create the pulse streams, or higher level modules like this which don't use step/dir signals:

https://www.sparkfun.../products/10859

Paul listed my top ask.

I'm currently using Arduino R3 protoshields.  They are pretty nice, but my perfect protoshield would have the entire perfboard area covered with either DIP style traces or groups of 3 pins tied together.  I hate linking pins on normal perfboard.

I'd also like if there were 2 or 3 holes tied to every pin that is brought up from the Netduino.  It's annoying to make a mini-bus somewhere to pull off 3.3V and send it to multiple support chips.

Actually, that ProtoX shield looks pretty close to my dream shield.  I just want one with the R3 pinout that brings up I2C pins for the N+2.  It also reminds me of one other nice idea, which would be the possibility to jumper all of the VCC lines for auxiliary circuits to be 3.3V or 5V.  They have a VCC line running next to ground, but it isn't tied to either.  

Chris: Any updates on this?  I've seen a few other I2C threads pop by too.

In the meantime I've ordered a Netduino 1 (a couple of days before the Netduino 2 announcement) and the I2C on there is working just fine with this device.  I won't be able to test this soon on my Netduino Plus 2 because it will be secured away into device.

No, I have the same failure using 3.3V as 5V.  I've tried it both ways.

I don't have a schematic for the breakout board that I'm using, Adafruit doesn't appear to publish one.  Had I known better a week ago I'd have ordered this board:

http://www.pololu.co...og/product/2124

They have much better documentation and do publish the schematics.  Their schematic is here:

http://www.pololu.co...ure/view/0J4051

From board inspection it looks like Adafruit uses a similar schematic.  The Adafruit board is using 10k pullup resistors (instead of 4.7k) and uses a single capacitor to handle noise on Vin instead of the 4 on the Pololu board.  I don't have a meter that allows me to measure the capacitance values to see if they match on the two boards.