Changing the degrees the BeInMotion kit rotate

So far I'm new in programming FPGAs and using the Quartus , Qsys and Nios. I tried to change all the values in the void turn_left() but returned empty handed. So far I'm grasping the basics but i'm pretty it is in that function. I want it to rotate from 90 degrees to around 45 deg. so that it will be smoother. Here's the code

int turn_left()

{

int dc_m1_pwm_duty = dc_m1_pwm_freq/4;

int dc_m2_pwm_duty = dc_m2_pwm_freq/4;

dc1_cmp = 1;

dc2_cmp = 1;

IOWR(IR_RX2_BASE,0x00,0);

IOWR(IR_RX1_BASE,0x00,0);

IOWR(DC2_PWM2_BASE+0x08,0,0);

IOWR(DC1_PWM1_BASE+0x08,0,0);

IOWR(DC2_PWM1_BASE,0,dc_m2_pwm_freq);

IOWR(DC2_PWM1_BASE+0x04,0,dc_m2_pwm_duty);

IOWR(DC1_PWM2_BASE,0,dc_m1_pwm_freq);

IOWR(DC1_PWM2_BASE+0x04,0,dc_m1_pwm_duty);

IOWR(IR_RX2_BASE,1,722);

IOWR(IR_RX1_BASE,1,722);

IOWR(IR_RX2_BASE,0x00,1);

IOWR(IR_RX1_BASE,0x00,1);

IOWR(DC1_PWM2_BASE+0x08,0,1);

IOWR(DC2_PWM1_BASE+0x08,0,1);

while(1)

{

if(( dc1_cmp ==0 ) && (dc2_cmp ==0 ))

return 0;

else

{

usleep(90000);

dc_m1 = IORD(IR_RX1_BASE,1);

dc_m2 = IORD(IR_RX2_BASE,1);

i = dc_m1-dc_m2;

j = dc_m2-dc_m1;

if(i > 5) {

if(dc_m2_pwm_duty >= 100)

dc_m2_pwm_duty-=50;

if(dc_m1_pwm_duty < 850)

dc_m1_pwm_duty+=50;

IOWR(DC2_PWM1_BASE+0x04,0,dc_m2_pwm_duty);

IOWR(DC1_PWM2_BASE+0x04,0,dc_m1_pwm_duty);

}

else

if(j > 5) {

if(dc_m1_pwm_duty >= 50);

dc_m1_pwm_duty-=50;

if(dc_m2_pwm_duty < 1700)

dc_m2_pwm_duty+=50;

IOWR(DC2_PWM1_BASE+0x04,0,dc_m2_pwm_duty);

IOWR(DC1_PWM2_BASE+0x04,0,dc_m1_pwm_duty);

}

}

}

}

Hope someone and I'll appreciate it. Thank you in advance.