Merge pull request prusa3d#3467 from gudnimg/autostart_stilltocheck-optimisation

Optimise `autostart_stilltocheck` variable

Author: leptun

Firmware/cardreader.cpp

@@ -30,7 +30,6 @@ CardReader::CardReader()
    memset(workDirParents, 0, sizeof(workDirParents));
    presort_flag = false;
 
-   autostart_stilltocheck=true; //the SD start is delayed, because otherwise the serial cannot answer fast enough to make contact with the host software.
    lastnr=0;
   //power to SD reader
   #if SDPOWER > -1
@@ -614,14 +613,17 @@ void CardReader::write_command_no_newline(char *buf)
 
 void CardReader::checkautostart(bool force)
 {
+  // The SD start is delayed because otherwise the serial cannot answer
+  // fast enough to make contact with the host software.
+  static bool autostart_stilltocheck = true; 
   if(!force)
   {
     if(!autostart_stilltocheck)
       return;
     if(autostart_atmillis.expired(5000))
       return;
   }
-  autostart_stilltocheck=false;
+  autostart_stilltocheck = false;
   if(!cardOK)
   {
     initsd();

Firmware/cardreader.h

@@ -133,8 +133,6 @@ class CardReader
   ShortTimer autostart_atmillis;
   uint32_t sdpos ;
 
-  bool autostart_stilltocheck; //the sd start is delayed, because otherwise the serial cannot answer fast enought to make contact with the hostsoftware.
-  
   uint16_t nrFiles; //counter for the files in the current directory and recycled as position counter for getting the nrFiles'th name in the directory.
 
   bool diveSubfolder (const char *&fileName);