RE: DRV8823 Control

Hi Rick,

Stepper motor used in the project is having 1.8 degrees angle for Fullstep.

Following is the code that is used to rotate the stepper motor.

U8 full_mseq_A_B[16] = {
    0xCF,0x03,
    0x1F,0X00,
    0X4F,0X03,
    0X4C,0X07,
    0X4D,0X03,
    0X1D,0X03,
    0XCD,0X03,
    0XC0,0X07
    };

void rotate_Motor(U8 dir, const F32 angle_to_rotate)
{
static U8 index_temp =0;
F32 i = 0.0;

    for(i = 0.0;i <= angle_to_rotate;i=i+0.9)
    {
        if( dir )
        {
          if( index_temp < 7 )
          index_temp++;
        else          index_temp = 0;
        }
        else
        {
          if( index_temp > 0 )
            index_temp--;
          else
          index_temp = 7;
        }
        //Send the data on SPI communication to Stepper motor driver
        Spi_Session_Layer_write(&full_mseq_A_B[index_temp*2],2);
        delay_ms(1);
    }

}

For 360 degree rotation, there is no issue.

void main(void)

{

rotate_motor((U8)1, 360);

while(1)  {   }

}

Following code is not working as expected, (expected is to shift 90 Degrees, but there is, minute deviation in the angle(starting from 0 degrees to 90 degrees)

This deviation is more if rotate_motor((U8)1, 45) function is called for 5 or 6 or 7 or 8 times before while(1)).

void main(void)

{

rotate_motor((U8)1, 45);

rotate_motor((U8)1, 45);

while(1){}

}

Please do needful in understanding why there is a deviation in angle , if the function rotate_motor((U8)1, 45) is called for 8 times.(expected is to rotate 45 degrees * 8  = 360 degrees),

But motor is rotating >352 degrees and < 360.degrees.(what is the exact error angle is not known).

Thanks

Rakesh