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HELP: A4983 + Motor Stepper

Hi,

I would to drive my motor with specific steps.

I bought the board A4983, and I connected in this way Microcontroller (Arduino Mega) with Polulu A4983 and my motor HY 200 2220 0100 AX 08 (see image).

With Enable High, every time I distribute Program in Arduino board, motor began to move (more than one turn) and after it stops (touching motor with fingers, it isn’t blocked).
I tried to regulate the potentiometer on A4983. I set 3.0 Vdc on Vref pin (the Arduino output is 5Vdc).

After I change Enable (Low), motor doesn’t runs, and after some minutes, A4983 board began to burn!

The code is:

int PinDir =  30;     // DIR
int PinStep =  31;    // STEP
int PinSleep =  32;   // SLEEP negato
int PinReset =  33;   // RESET negato
int PinMstre =  34;   // MS3
int PinMsdue =  35;   // MS2
int PinMsuno =  36;   // MS1
int PinEnable =  37;  // ENABLE negato
int PinVref =  38;  // VREF
int PinLed =  13;  // led

void setup()   {                
    pinMode(PinDir, OUTPUT); 
    pinMode(PinStep, OUTPUT); 
    pinMode(PinSleep, OUTPUT); 
    pinMode(PinReset, OUTPUT); 
    pinMode(PinMstre, OUTPUT); 
    pinMode(PinMsdue, OUTPUT); 
    pinMode(PinMsuno, OUTPUT); 
    pinMode(PinEnable, OUTPUT); 
    pinMode(PinVref, OUTPUT);
    pinMode(PinLed, OUTPUT);
    
    digitalWrite(PinMsuno, LOW);   // setto MS1 alto
    digitalWrite(PinMsdue, HIGH);   // setto MS2 basso
    digitalWrite(PinMstre, LOW);   // setto MS3 basso
  
    digitalWrite(PinEnable, LOW);   // setto Enable alto
    digitalWrite(PinReset, HIGH);   // setto Reset alto
    digitalWrite(PinSleep, HIGH);   // setto Sleep alto 
    digitalWrite(PinVref, HIGH);   // setto Vref alto   
  
    delay(2);
    digitalWrite(PinDir, HIGH);
    delay(2); 
}

void loop()                     
{   
      digitalWrite(PinStep, LOW);
      digitalWrite(PinLed, LOW);
      delay(20);
      digitalWrite(PinStep, HIGH);
      digitalWrite(PinLed, HIGH);
      delay(20); 
}

Which are the problems? Please help me. Thank you.
HY 200 2220.pdf (215 KB)


Hello.

It looks like you are trying to drive the REF pin high, which could damage the motor driver. The point of the REF pin is for you to be able to look at the current limit setting. Also, the point of this version of the carrier with the regulators is that you don’t need the external 78L05 regulator; you can just connect the 5V pin (an output) to VDD.

- Jan

Hi,
I have removed the Regulator. The A4983 VDD Pin is connected to 12Vdc. (See image attached)

1)“The point of the REF pin is for you to be able to look at the current limit setting”: what it means? Please, if you can, explain to me?
2)If I buy another A4983 board, and I connect circuit as picture, works it fine?
3)In which way can I set opportunely the potentiometer?
4)The software code is ok?
Thank you.
Ivano


Hello.

Connecting 12V to VDD is a good way to destroy the board. You need to be much more careful when using devices like this; make sure you understand what you’re doing before you make your connections! Jan’s instructions were: “you can just connect the 5V pin (an output) to VDD”. If you supply 12V to VMOT, you can power the logic side of the board by connecting the 5V pin (just above VDD) to VDD.

- Ben

Hi,
Ok, I connect 5 VDC on VDD.
For other questions:
1)“The point of the REF pin is for you to be able to look at the current limit setting”: what it means? Please, if you can, explain to me?
2)If I buy another A4983 board, and I connect circuit as picture, (with 5VDC on VDD) works it fine?
3)In which way can I set opportunely the potentiometer?
4)The software code is ok?
Thank you.

?? :frowning:

Hello.

I am not sure what your last post ("?? :frowning:") is supposed to communicate, but it comes off as somewhat annoying when it’s on a Sunday. Anyway, here are some responses to your questions:

  1. We try to explain it some on the product page, and it is also covered in the datasheet. We do not want to spend more time on it with you if you do not indicate that your are reading what we already wrote.

  2. Probably. There are all kinds of ways you can destroy products like these, so we cannot guarantee things will work for you.

  3. I don’t really see how this is different from question 1. One thing you can do without putting much effort into understanding anything is to just put it in the middle of its range; the driver will probably do something then. Once you have it moving the motor, you can try moving the pot to either side to see the effect it has on your motor.

  4. Maybe. This is similar to question 2, where there is any number of ways you could have small mistakes in it. We are not going to carefully look through your code when you have major electrical mistakes that will most likely prevent operation. Once you have more reasonable connections, the code probably will work, or you will probably be able to find what is wrong with it.

- Jan

Dear Site Administrator Jan,
Sorry but I don’t like your last message.
If you are tired to answer questions about this Forum, it’s an your problem, and please don’t give vent to featureless answers.
The question can be stupid, without meaning and repetitive, FOR YOU, but not for who writes.

You wrote 1)2)3)4) considerations without any technical word for solve my problem.

Sorry for Sunday, but in Italy was Monday, at morning!

I’m an Engineer, and every time I buy a new device, I read datasheet and I try to understand its working.
This time, I have read datasheet very fast. I connected wires like my first post, and A4983 burned.

I will read datasheet with more care.

Sorry for bother.

Goodbye.
Ivano.
a4983_DMOS_microstepping_driver_with_translator.pdf (360 KB)

I am not sure how much I can trust the time stamps on the forum, but wasn’t your post at something like 1:30 Monday morning your time?

I did not indicate anything about being tired of answering questions on the forum or your questions being stupid. However, I do want to let you know when your expectations are unreasonable, like getting annoyed that no one is answering your questions on a Sunday.

Finally, I did give you some specific technical advice; the point of the less technical responses was to let you know that you were expecting too much: we are not going to go through all the details of your design when there are major problems that explain why it’s not working.

- Jan