View source for KS0378 Keyestudio Reprap Stepper Driver A4988 Kit (5PCS)

[[image:ks0378.png|thumb|600px|right|Keyestudio UNO R3 Board]]

==Introduction==
This stepper motor driver is powered by A4988, a DMOS microstep driver with converter and over-current protection. 
It is available in full, half, 1/4, 1/8 and 1/16 stepping modes to operate bipolar stepper motor with output drive performance up to 35 V and ± 2A. 
The A4988 includes a fixed turn-off time current regulator that operates in slow or mixed decay mode.
The converter is the key to implement the A4988. As long as the "step" input carries in a pulse, it can drive the motor to produce micro-step. 
There is no need for phase sequence tables, high frequency control lines or complex interface programming. 
The A4988 interface is ideal for complex microprocessors that are not available or overloaded.


==Specifications==
1. With only simple step and direction control interface;
2. Five different step modes: full, half, 1/4, 1/8 and 1/16;
3.Adjustable potentiometer can adjust the maximum current output, resulting in a higher step rate;
4. Automatic current decay mode detection / selection;
5. Overheat shutdown circuit, undervoltage lockout, cross current protection;
6. Ground short circuit protection and load short circuit protection.


==Settings for working mode==
<br>[[Image:ks0378-1.png|600px|frameless]]<br>


==Connection Diagram==
It needs to connect DC 8-15V between motor power VMOT and GND.
<br>[[Image:ks0378-2.png|600px|frameless]]<br>


==Sample Code==
<pre>
int dirPin = 7;
int stepperPin = 8;
void setup() {
pinMode(dirPin, OUTPUT);
pinMode(stepperPin, OUTPUT);
}
void step(boolean dir,int steps){
digitalWrite(dirPin,dir);
delay(50);
for(int i=0;i<steps;i++){
digitalWrite(stepperPin, HIGH);
delayMicroseconds(800);
digitalWrite(stepperPin, LOW);
delayMicroseconds(800);
}
}
void loop(){
step(true,1600);
delay(500);
step(false,1600*5);
delay(500);
}
</pre>


==Test Result==
The selection end MS1, MS2, MS3 of three modes are all connected to GND, that is, full-step mode, and the motor needs 200 stepping values or a stepping 1.8° to turn a round.
In the experiment, we first let the stepper motor reverse 8 circles and delay 0.5 seconds; then turn 40 circles and delay 0.5 seconds. 
If it is an half-step mode, then the number of both positive and reverse circle should be halved.


==Package Included==
* Keyestudio Reprap Stepper Driver A4988 *5PCS
<br>[[Image:ks0378-3.png|600px|frameless]]<br>


[[Category: Arduino Board]]