Using stepper motor with LPC1768 and L293D motor controller

Mbed OS Hello world!
1

I’m trying to control a stepper motor (42shdc3025-24b) NEMA17, but it seems to vibrate back and forth. Im trying to use my own class/library system so that i understand its functions better but havn’t managed to get anywhere with it.

Blockquote
#include “mbed.h”

Serial pc(USBTX, USBRX);

class MyStepper
{
public:
MyStepper(PinName APin, PinName BPin, PinName CPin, PinName DPin);
void write(int A, int B, int C, int D);
private:
DigitalOut _APin;
DigitalOut _BPin;
DigitalOut _CPin;
DigitalOut _DPin;
};
MyStepper::MyStepper(PinName APin, PinName BPin, PinName CPin, PinName DPin)
: _APin(APin), _BPin(BPin), _CPin(CPin), _DPin(DPin)
{
}
void MyStepper::write(int A, int B, int C, int D)
{
_APin = A;
_BPin = B;
_CPin = C;
_DPin = D;
}

MyStepper stepper1(p21,p22,p23,p24);
int LoopState = 1;
int StepTime = 0.5;

int main()
{
pc.printf(“connected!\n”);
stepper1.write(0,0,0,0);

while(true) {
    switch(LoopState) {
        case 1:
            pc.printf("Case 1");
            stepper1.write(1,0,0,0);
            wait(StepTime);
            LoopState+=1;
            break;
        case 2:
            pc.printf("Case 2");
            stepper1.write(0,1,0,0);
            wait(StepTime);
            LoopState+=1;
            break;
        case 3:
            pc.printf("Case 3");
            stepper1.write(0,0,1,0);
            wait(StepTime);
            LoopState +=1;
            break;
        case 4:
            pc.printf("Case 4");
            stepper1.write(0,0,0,1);
            wait(StepTime);
            LoopState=1;
            break;
    }
}

}

2

Hello,

please be so kind and use correct code formatting. Place these symbols ``` before and after your code.

  • It needs some specific pulses and not like this, it must be much faster, I think.
  • Here you can see how it is done in Arduino library Stepper.h.
  • The printf is slow function so it will also slow down the while loop.

BR, Jan