Stepper motor does not turn

Other Hardware Motors, Mechanics, Power and CNC
3

Robin2:
You have not posted your program or your circuit diagram.

The Pololu A4988 web page has a good circuit diagram - and lots of other useful info.

Try this Simple Stepper Code

...R
Stepper Motor Basics

My circuit:

Vmot/GND --> 12V 2A
VDD/GND --> Arduino 5V/GND
Step --> Arduino D5
Dir --> Arduino D6
Sleep with Reset

Motor
Black (A) --> 1B
Green (A/) -->1A
Red (B) --> 2A
Blue (B/) --> 2B

My Code:

int ste = 5;
int dir = 6;

void setup()
{
pinMode(ste, OUTPUT);
pinMode(dir, OUTPUT);
}

void loop()
{

for(int i = 0; i < 400; i++ )
{

digitalWrite(dir, HIGH);
digitalWrite(ste, HIGH);
delay(250);
digitalWrite(ste, LOW);
delay(250);
}

for(int i = 0; i < 400; i++ )
{
digitalWrite(dir, LOW);
digitalWrite(ste, HIGH);
delay(250);
digitalWrite(ste, LOW);
delay(250);
}

}

Is there are mistake in the connection of the motor to the driver?