stepper motor

[jorj]

I have a stepper motor that when I give an order to turn to one side it turn without any problem but if I give an order to turn to the opposite side the motor turn to the two sides simultaneous
When I add a capacitor in the input of the line of control , the problem disappear
Why it happen

[sonictj]

Before anyone can really help you, you have to tell us what specific hardware your using to drive the stepper.  At the moment I can't really guess until I have more information.

[jorj]

i use the controller atmega162 (ATMEL)

[Webbot]

You must presumably be using some extra hardware between the ATMega162 and the actual motor.

Are you producing the stepper motor signals from within the ATMega162 ie in software or are you using a stepper driver IC to produce them for you?

If you're doing it in software then you may be producing the signals for the coils in the wrong way for one direction.

[jorj]

i do it in a software but i think that the problem is not in the software

[GearMotion]

i do it in a software but i think that the problem is not in the software

Slow it way down and put some LEDs on it. Is the pattern right?

[Webbot]

Try reversing the wires to the stepper coils. If you find that the motor now turns correctly the other way, and the previously ok direction now fails then I can almost guarantee that its either your software waveform being wrong or your wiring to the stepper coils being wrong.