如何使用看门狗定时器以及如何在我的代码中超时函数

大家好。我目前正在使用PIC18K22F97进行直流电机控制。我还使用一个LITLE ARDUNO tiN来实现对电机的速度和电流的数据采集，数据由UART发送。在我的PIC中，在我的主控制循环中，我所做的是（在其他的OFC之间）：请求小工具等待数据，一旦数据被接收，它被存储在我的一个全局变量（In16t电流或In16t速度）中，并被用在PID调节中。我所写的用于获取数据的函数称为GETXQualAuthor（和GETZVITESSER）；VITESE是法语中的速度，这是我的函数的代码（基本上都有相同的代码）：USATAR1ISISRXARRADYY（））{CurrANT1= EUARTAR1Read（）；}（EUARTAR1IISTXXRead（））{EUARTAR1X写（0B000 000））；}（EUARTAR1IISRXA Read y（））{CurrANT2= EuSART1Ia Read（）；}（校验位（Currut1,7））{BITYLCR（CURANT1,7）；CURANTY＝（CURANT1和LT；LT；8）CurANT2；CouTou2；ITE（0B000 000 01）；RANT = -Curnand；} {Curnal=（Currand 1＆lt；lt；8）} CurANT2；}返回Curnand；}这里是我的一个主要程序：{StullFig旗）{int i＝0；do{MeSuru-Curnal= GeTyCouthAuthor（）；张弛初始= PIDL Currand（Meurur-Curnter，Erurura Currand，CasigeNeURCurnor，TimealeE-Curnand，KpCurrand，KiCurnand，KdCurrand，WordNuPuth-Fravig-Currand）；I++；PuthRaPrPosixCyclik（张弛初始，CouxxMyMod）；}（i）；10）这个循环需要以一个恒定的速度运行。我的问题是：如果我的小饰品没有及时回复，GETSQualAuthor（），将无限期地等待，因此停止我的控制，这是我不能让它发生的。我想做的是：在调用GETSqurAuthor（）之前启动一个定时器；10，函数没有完成（因此，如果新的当前值没有被存储），我想跳过GET-CurrAuthor（），并让变量变成旧的值，所以MeSuriCurand将保持不变，并且控制可以继续（下一个指令，PID函数），我是一个C语言初学者。在读了我的代码之后，你可能已经注意到了。我对XC8和PIC也不太熟悉。你能告诉我怎样才能得到我想要的吗？另外，如果你有任何建议，使我的代码更快，请不要犹豫。如果我没有使自己足够清楚，我很乐意进一步解释我的问题。谢谢大家。



      以下为原文

    Hello everyone.
I am currently using PIC18K22F87 for dc motor control.
I am also using a litle arduino trinket to realize the acquisition of the data regarding the speed and the current of the motor.
The data is sent by UART. (I set up the uart with MCC as asynch with 9800 Bauds).
On my pic, what i do in my main control loop is (between others, ofc):

• Ask the trinket for data
• wait for response
  

Once the data is received, it is stocked in one of my global variable (int16_t current or int16_t speed) and is used in PID regulation.
The functions I wrote to get data are called get_courant(); and get_vitesse();          Vitesse means speed in french

Here is the code of my functions (both basically have the same code):

int16_t get_courant()
{
uint8_t courant1;
uint8_t courant2;
int16_t courant;

if(EUSART1_is_tx_ready())
   {
      EUSART1_Write(0b00000001);
   }
if(EUSART1_is_rx_ready())
   {
      courant1= EUSART1_Read();
   }

if(EUSART1_is_tx_ready())
   {
      EUSART1_Write(0b00000010);
   }
if(EUSART1_is_rx_ready())
   {
      courant2= EUSART1_Read();
   }
if (CheckBit(courant1,7))
   {
      bit_clr(courant1,7);
      courant = (courant1 << 8) | courant2;
      courant = - courant;
   }
else
   {
       courant = (courant1 << 8) | courant2;
   }

return courant;
}


And here is a piece of my main programm :


while(!Stop_flag)
{
    int i=0;
    do
    {
Mesure_courant=get_courant();
Tension_initiale =                                    PID_Courant(Mesure_courant,Erreur_courant,Consigne_courant,Integrale_courant,Kp_courant,Ki_courant,Kd_courant,Wind_up_flag_courant);
i++;
Put_Rapport_Cyclique(Tension_initiale, Choix_Mode);

} while(i<10);


This loop needs to run at a constant speed.
My problem is : at the moment, if my trinket doesn't reply in time,  get_courant(); will wait indefinitely, hence stoping my control, which I cannot let happen.

What I would like to do is the following :

• Start a timer before calling get_courant();
• If after 10 us, the function is not completed (so if the new current value isn't stocked) I want to skip get_courant(); and let the variable to it's old value, so Mesure_courant will stay the same, and the control may continue (go to the next instruction, the PID function)
  

I'm a beginner with C langage (as you may have noticed after reading my code).
I'm also not very familiar with XC8 and PIC in general.


Can you explain to me how to acheive what I want?

Also, if you have any suggestions to make my code faster, please don't hesitate.

If  I didn't make myself clear enough, I would be delighted to explain my problem further.

Thank you all.