Hi,
My stepper motor only vibrates (move 1 step forward and back, the speed of vibration can be controlled), but it does not rotate. Could it be due to low voltage? Out of the 5 trials, it made rotations once, but when I restart the system the next day, it fails again. No change in my code/setup.
Stepper Motor (6wires)
-1.8deg/step
-6.48V
-1.2A
Power Supply
-12V
-1.5A
I build my setup according to this: Example 1 Setup, Example 7 Code
Any help is appreciated! 
The Easydriver has a max current of 0.75 amps. You say your motor needs 1.2 amps - you need a BigEasydriver.
Have you correctly connected 4 of the 6 motor wires to the driver? The two wires that go to the centres of the coils should not be connected to anything - not even to each other.
What motor power supply are you using (volts and amps)?
This Simple Stepper Code
should work with any driver that needs step and direction signals.
...R
Stepper Motor Basics
You need to convince us you've wired it up correctly. That means you will have measured which
windings are which with a multimeter and corrected the ends of winding A to the A terminals,
the ends of winding B to the B terminals, and the centre-taps are both insulated from anything.
[A and B just have to be separate windings, it doesn't matter which winding you call A so long as you
then call the other winding B].
Hi all,
Thank you for the advice.
Yes, I have tested the 6 wires with the multimeter, and gotten the 2 matching pairs (coils).
I'm using a AC adaptor.
So, the problem lies with my easydriver? My application requires me to control the stepper motor in 3 different speed. I don't need it to run at its max capacity, bought this 2nd-hand stepper.
Tried again, this time my motor only can turn in one direction, despite reversing the sign to -1.
Thanks in advance.
bearine:
Tried again, this time my motor only can turn in one direction, despite reversing the sign to -1.
That sounds like useful progress. But if you want help you must post your latest code.
...R
Hi,
Have you tried reversing the coil A connections, so the current goes through it in the opposite direction with respect to coil B.
It may be a phasing problem.
Tom... 
TomGeorge:
Hi,
Have you tried reversing the coil A connections, so the current goes through it in the opposite direction with respect to coil B.
It may be a phasing problem.Tom...
No that will only reverse the direction. You can reverse the A pins, the B pins or completely swap the
A winding with the B winding and all that happens is the starting phase and direction change. So long
as each winding goes each side of th driver it will sequence.
My guess is the current hasn't been set large enough (it should work, albeit not very powerfully, from
0.7A - it won't work if you've got the driver set up at 0.1A or something tiny).