CNC Shield with DRV8825 Not Working

Other Hardware Motors, Mechanics, Power and CNC
1

I am using a CNC Shield as pictured below with a DRV8825 driver attached.
I tuned the current limiter on the DRV8825 to about .2A as specified by my motor's spec sheet.
When I turn on the 12V power supply, the motor makes a beeping sound but does not move.
I am currently using no jumpers and am on standard stepping (no microstepping).

I know this motor works because I have a different driver that it will work on but makes quite a lot of noise with, hence the reason I am trying the CNC shield with DRV8825.

Here is the code I am running:

#define EN        8  

//Direction pin
#define Y_DIR     6

//Step pin
#define Y_STP     3  


//DRV8825
int delayTime=300; //Delay between each pause (uS)


void setup(){

  pinMode(Y_DIR, OUTPUT); pinMode(Y_STP, OUTPUT);
  pinMode(EN, OUTPUT);
  digitalWrite(EN, LOW);

}

void loop(){
    digitalWrite(Y_STP, HIGH);
    delayMicroseconds(30); 
    digitalWrite(Y_STP, LOW);
    delayMicroseconds(delayTime);

}

Also attached is a PDF of the motor data sheet and here is where I purchased it: https://www.omc-stepperonline.com/nema-8-stepper-motor/nema-8-bipolar-18deg-16ncm-23ozin-02a-48v-20x20x28mm-4-wires-8hs11-0204s.html

Any help would be greatly appreciated!!

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2

Start with your motor running 1000 times slower. Instead of delayMicroseconds(delayTime); try delay(delayTime);

...R
Stepper Motor Basics
Simple Stepper Code

3

No more beeping, but there is a very faint hiss if I get my ear close to it.
Still no movement.

In my experience, delayMicroseconds(100) is an OK speed with my other driver.

4

AndrewKamp:
No more beeping, but there is a very faint hiss if I get my ear close to it.
Still no movement.

Please post the latest version of your program so we can see exactly what you have done.

Are you sure you have all the pins defined correctly?

What other driver do you have? And how is it connected to the Arduino?

...R

5

Thank you for setting me on the right track with the delay time. Seems this driver has a much different delay time that will make it move.
I settled on a range of delayMicroseconds(1000) - delayMicroseconds(450).

There is one caveat however: To make the motor move at all fast I had to tune the DRV8825's current limiter much higher than the spec sheet said to do.
Spec sheet says .2A, but I had to increase the DRV8825 limiter to .21VDC (which means the current limiter is .42A).

6

AndrewKamp:
Thank you for setting me on the right track with the delay time. Seems this driver has a much different delay time that will make it move.

Sorry, but that does not make sense. And you have not answered my question about what other driver you were using.

There is one caveat however: To make the motor move at all fast I had to tune the DRV8825's current limiter much higher than the spec sheet said to do.
Spec sheet says .2A, but I had to increase the DRV8825 limiter to .21VDC (which means the current limiter is .42A).

The setting depends on the value of the current-sense resistor. Maybe the module you have has a different resistor? The Pololu DRV8825 web page has a lot of info about setting the current limit and other things.

...R

7

What is the voltage and current capability of the motor power supply?