下面程序大家有没有懂的，帮忙注释一下，谢谢了
int16_t inputValue;
  if(SysTickFlag)
  {
  angle = MMA7455_Angle();
   if( angle < 100){
   Insert_Angle(angle);
  // Digit_Set(ANGLE_POS0, g_angle/10);
         LCD12864_SetXY(1,6);
  LCD12864_PutNumber(g_angle/10);
  // Digit_Set(ANGLE_POS1, g_angle%10);
         LCD12864_SetXY(1,7);
  LCD12864_PutNumber(g_angle/10);
    if(System_Function == 1){
    //inputValue = pid_Controller(20, g_angle, &pidData);
     //Set_Input(inputValue);
     if(g_angle > 45)
     {
     pwm_value = 512 - (int16_t)(g_angle - 45)*15;
      if(pwm_value < 0)        pwm_value = 0;  
    }
    else if(g_angle < 45)
    {
     pwm_value = 512 + (int16_t)(45-g_angle)*15;
      if(pwm_value > 1023)       pwm_value = 1023;     }
    PWM_OutPut(pwm_value);    }
   else if(System_Function == 2){
    inputValue = pid_Controller(SettingAngle, g_angle, &pidData);
    Set_Input(inputValue);    }
   }  
 }
 }

#include "Message.h" #include "SysTimer.h"  
enum KScanState{
    KSCAN_IDLE = 0,         /* 无键按下, 键盘扫描初始状态 */
     KSCAN_PRESS,            /* 键按下，判断抖动, 键按下>40ms */
     KSCAN_NORMAL,   /* 普通按键，判断是否长按键，键按下>1.6s */
     KSCAN_LPRESS,         /* 长按键，判断是否连发，键按下>1s */
    KSCAN_LIANFA,           /* 连发按键，判断连发，每0.4s一次连发按键 */ };  
struct KStateFsm{
    enum KScanState kpress_next;  /* 键按下，下一个状态 */
     enum KScanState nokey_next;   /* 键抬起，下一个状态 */
    unsigned char kpress_time;   /* 键按下需持续的时间, 20ms的倍数 */
    enum KeyType ktype;     /* 键按下满足条件，输出按键类型 */ };  
/* 状态转换表，保证状态编号值与在数组中的位置相同  */
 struct KStateFsm kstate_fsm_table[] = {
/* current          kpress_next,  nokey_next,  time,   type   */
 /* KSCAN_IDLE   */ {KSCAN_PRESS,  KSCAN_IDLE,  1,   eKTYPE_NOKEY},
 /* KSCAN_PRESS  */ {KSCAN_NORMAL, KSCAN_IDLE,  2,   eKTYPE_NORMAL},
 /* KSCAN_NORMAL */ {KSCAN_LPRESS, KSCAN_IDLE,  80,  eKTYPE_LPRESS},
 /* KSCAN_LPRESS */ {KSCAN_LIANFA, KSCAN_IDLE,  50,  eKTYPE_LIANFA},
 /* KSCAN_LIANFA */ {KSCAN_LIANFA, KSCAN_IDLE,  20,  eKTYPE_LIANFA} };  
static enum KScanState keystate; static unsigned char oldkey;
static unsigned char ktime_counter = 0;
static pFunKeyRead KeyRead_CallBack;  /* 回调函数, 读按键，返回按键编号 */
void KeyScan_Run20ms(void) {
 unsigned char key_id = 0;
  struct MSG msg;  




  
 if(!KeyRead_CallBack)   return;  
 key_id = (*KeyRead_CallBack)();  
    if( (key_id != 0) && (key_id == oldkey) )
    {
        if(++ktime_counter >= kstate_fsm_table[keystate].kpress_time )
        {
            ktime_counter = 0;
   if(eKTYPE_NOKEY != kstate_fsm_table[keystate].ktype)
            {
    msg.msg_id = eMsg_Key;
     msg.parma_len = 2;
    msg.parma.data[0] = key_id;
    msg.parma.data[1] = kstate_fsm_table[keystate].ktype;
     Msg_PushMessage(&msg);
             }
   keystate = kstate_fsm_table[keystate].kpress_next;
         }
     }     else
    {
        keystate = kstate_fsm_table[keystate].nokey_next;
         oldkey = key_id;     }
 }
好多程序啊，晕乎乎的，谢谢大家了