http://www.sparkfun.com/commerce/produc … ts_id=8420
picture shows 6 pins,
datasheet says there are only 4 ones that need a connection :s
what do i need to do?
How do i drive it?
Are the other pin’s not connected ?
I guess it’s a bipolar stepper?
chrome,
That stepper motor can be run in either bi-polar mode or uni-polar mode (all 6-wire stepper motors can do either mode). If you run it bi-polar, you don’t use the center taps from each phase (thus only 4 of the 6 wires are used).
The EasyDriver stepper driver is only for bi-polar motors. So if you wire up the stepper in bi-polar mode, it will work just dandy with the EasyDriver.
You just leave the two center tap pins unconnected.
*Brian
http://triindia.co.in/resources_images/ … ematic.jpg
Like that?
If that is the case, isn’t a unipolar simpler to use with a micro controller.
chrome,
Yup, you’ve got it.
If you drive the coils independently with pins on your micro, then yes, it could easily be argued that unipolar is ‘easier’. However, if you use a stepper driver chip (which you probably want to use, especially if you are trying to get the best performance out of the stepper, so you will want to use a very high coil voltage and use a chopper driver chip) then the two pins of STEP and DIRECTION are the simplest by far. There are stepper driver chips for both uni-polar and bi-polar - depending upon the exact application, wiring a motor in bi-polar mode will give slightly better performance. (And there are fewer wires going out to the motor.)
Really, you can do it either way. 
*Brian
Well the stepper driver isn’t available yet :s
Also are you sure ? Did you buy one?
I don’t want to buy them (3) and see that it doesn’t work.
chrome,
I designed that stepper driver - I have many of them at home and they’ve all worked just great. If you wire up the motor bi-polar, it will work great with the EasyDriver. You just need to wait until SparkFun can get more of them built.
*Brian
Ah good, yeah too bad they don’t have any, I’m not really the type to wait that long, also a shame that it only drives 5V , guess i’ll have to use some mosfet’s.
the idea basicly was a cnc
chrome,
I think you’re taking the 5V spec wrong. The EasyDriver is rated to drive up to 30V into the stepper motor. And I’m running CNC routers using four EasyDrivers with a PC power supply (12V) and they work absolutely awesome. (Well, not as fast as bigger power supplied, but I don’t need to go fast.)
Check out http://greta.dhs.org/FrostBot to see one CNC application of EasyDriver boards.
*Brian
oh yeah 
So i can have my own power supply to have the needed power for the motor?
chrome,
The way the EasyDriver (or any driver like it) works is that you supply it with “motor power”, which for the ED can be anywhere from about 9V to 30V. The driver chips also need 5V, which is supplied with a little 5V regulator on the board. So all you give it is Motor Power, and the two input signals (step and direction) and then the four wires to the motor. Easy as could be. Two I/O bits per motor, you can daisy chain the Motor Power inputs between many Easy Driver boards.
*Brian
EmbeddedMan or anyone,
After reading this discussion, I am still uncertain. Could you specifically state which of the 6 pins of the SparkFun stepper motor connect to which pads of the EasyDriver? Which pins are left open? I am driving the whole thing with an Arduino.
Thanks,
weinerdog
I also have a question about the easy driver, i understand the step input (each pulse makes it “turn” 1 step?), but the direction input, how does it work?
1 means right, 0 left?
chrome,
Yup, you’ve got it exactly right. If DIR is HIGH and the driver sees a rising edge on STEP, then it will take one step CLOCKWISE*. If DIR is LOW during the rising edge of STEP, then it will take one step COUNTER-CLOCKWISE*.
*Note that these directions are not exactly meaningful - just that they are opposite. The reason is that if you reverse the wiring to the two windings of the motor, it will turn in the opposite direction, or if you reverse the wiring to either one of the phases, it will turn in the opposite direction, etc. So it is not truthful to say clockwise or counterclockwise, as it will really depend exactly upon your wiring. However, the point of all of this is that the DIR signal determines which way (call them ‘one way’ and ‘the other way’) it turns on each step.
*Brian
weinerdog,
OK, here is what I think will work. Based upon the EasyDriver board layout and the stepper motor data sheet.
ED Motor
1 A
2 C
3 B
4 D
Note that, as per the motor datasheet, there will be a pin between A and C and another one between B and D that go unused on the motor connector itself.
Does this make sense?
*Brian
Hello all,
I’m a bit new with steppers and Arduino. Could someone explain how the connection is made to an Arduino board. I have a four wire motor connected to the pin A B C D on the ED, power and ground are established, does the step input and direction input get connected to the an Arduino board digital input pins. (i.e. input pin 8 and 9).
hsub.
You will need to connect the STEP and DIRECTION pins on the EasyDriver to outputs on the Arduino. You will also have to connect ground from the Arduino to the EasyDriver. Then you should be all set! Pulse that STEP pin and your motor should move.
*Brian