in str/ev3-api/library/libcpp-ev3/src/Motor.cpp [31:43]
void Motor::setPWM(int pwm)
{
mPWM = (pwm>PWM_MAX)? PWM_MAX:((pwm<PWM_MIN)? PWM_MIN:pwm);
if (mBrake == true && pwm == 0)
{
ev3_motor_stop(mPort, true);
}
else
{
ev3_motor_set_power(mPort, mPWM);
}
}