位置式PID与增量式PID

//位置式PIDfloat Kp;
float Ki;
float Kd;float eSum,e0,e1;float pid_control(float now,float target)
{
    float pe,ie,de;
    float out;    e0 = target - now;
    eSum += e0;    pe = e0;
    ie = eSum;
    de = e0 - e1;    out = pe*Kp + ie*Ki + de*Kd;    out = limit(out,-LIMIT,LIMIT);    e1 = e0;    return out;
}//增量式PIDfloat Kp;
float Ki;
float Kd;float eSum,e0,e1,e2;float pid_control(float now,float target)
{
    float pe,ie,de;
    float out;    e0 = target - now;    pe = e0 - e1;
    ie = e0;
    de = e0 - *e1 + e2;    out = pe*Kp + ie*Ki + de*Kd;
    out = limit(out,-LIMIT,LIMIT);    e2 = e1;
    e1 = e0;    return out;}