fixed loop data persistance

USBDrive_Airplane_Data_Logger/USBDrive_Airplane_Data_Logger.ino

@@ -51,6 +51,7 @@ bool LED_ON = false;
 
 
 // https://www.pjrc.com/teensy/td_uart.html
+// these buffers are used by the UART interrupt
 #define Serial1RxBufferSIZE 1024  // 10 seconds
 char Serial1RxBuffer[Serial1RxBufferSIZE]; // global scope or static char. power of 2. 
 
@@ -93,12 +94,15 @@ void setup()
 
   if (DEBUG) RTCDisplay();
 
+  // Serial1 Rx @ Tx (0), Tx @ Tx (1)
   Serial1.begin(9600); // MUST match Garmin
   Serial1.addMemoryForRead(Serial1RxBuffer, Serial1RxBufferSIZE);
 
+  // Serial2 Rx @ Rx1 (16), Tx @ Tx1 (17)
   Serial2.begin(115200); // MUST match Dynon EFIS
   Serial2.addMemoryForRead(Serial2RxBuffer, Serial2RxBufferSIZE);
 
+  // Serial3 Rx @ A1 (15), Tx @ A0 (14)
   Serial3.begin(115200); // MUST match Dynon EMS
   Serial3.addMemoryForRead(Serial3RxBuffer, Serial3RxBufferSIZE);
     
@@ -120,7 +124,7 @@ void setup()
   if (DEBUG) Serial.printf(F("      fs started: %d\n"), myDrive1.filesystemsStarted());
   
   if (DEBUG) Serial.printf("Find next file number...\n");
-  i=next_file_number();
+  i=next_file_number();  /* global access to myFiles1 */
   sprintf(fname,"Log%04d.txt",i);
   if (DEBUG) Serial.printf("Testing for file %s\n",fname);
   
@@ -144,7 +148,7 @@ void setup()
 
 
 
-int next_file_number() {
+int next_file_number() {  /* global access to myFiles1 */
   // returns the first unused file number
   char fname[16];
   bool fileexists = true; // assume true
@@ -251,55 +255,60 @@ time_t getdatetime(){
 }
 
 
+// loop is called repeatedly
+// static vars to persist between calls
 void loop(void) { 
   int i;
+  static int t=0;
   char fname[16];
-  int msg1 = 0;
-  int msg2 = 0;
-  int msg3 = 0;
-  int i1 = 0;
-  int i2 = 0;
-  int i3 = 0;
-  char  GPSRx[Serial1RxBufferSIZE];
-  char EFISRx[Serial2RxBufferSIZE];
-  char  EMSRx[Serial3RxBufferSIZE];
-  bool MSG_OVFL = false;
+  
+  // these buffers are used for message processing
+  static char  GPSRx[Serial1RxBufferSIZE];
+  static char EFISRx[Serial2RxBufferSIZE];
+  static char  EMSRx[Serial3RxBufferSIZE];
+  static int msg1 = 0;
+  static int msg2 = 0;
+  static int msg3 = 0;
+  static int i1 = 0;
+  static int i2 = 0;
+  static int i3 = 0;
+  static bool MSG_OVFL = false;
 
   
-  // process until end of message
+  // process until end of message or overflow
   if (Serial1.available()) {
     GPSRx[i1]=Serial1.read();
+    //Serial.print(GPSRx[i1]);
     if (GPSRx[i1] == GPS_EOM) msg1 = i1;
     i1++;
-    GPSRx[i1]=NULL;
     if (i1 == Serial1RxBufferSIZE - 1) {
       MSG_OVFL = true;
       msg1 = i1;
-    }
+    } else GPSRx[i1]=NULL;
   }
   
-  // process until end of message
+  // process until end of message or overflow
   if (Serial2.available()) {
     EFISRx[i2]=Serial2.read();
+    //Serial.print(EFISRx[i2]);
     if (EFISRx[i2] == EFIS_EOM) msg2 = i2;
     i2++;
-    EFISRx[i2]=NULL;
     if (i2 == Serial2RxBufferSIZE - 1) {
       MSG_OVFL = true;
       msg2 = i2;
-    }
+    } else EFISRx[i2]=NULL;
   }
   
-  // process until end of message
+  // process until end of message or overflow
   if (Serial3.available()) {
     EMSRx[i3]=Serial3.read();
+    //Serial.print(EMSRx[i3]);
     if (EMSRx[i3] == EMS_EOM) msg3 = i3;
     i3++;
-    EMSRx[i3]=NULL;
     if (i3 == Serial3RxBufferSIZE - 1) {
       MSG_OVFL = true;
       msg3 = i3;
-    }
+    } else EMSRx[i3]=NULL;
   }
 
 
@@ -341,6 +350,14 @@ void loop(void) {
     tick = false;
     toggleLED();
 
+    if (myFile) {
+      if (t>4) {
+        myFile.flush(); // flush every 5 seconds
+        t=0;
+      }
+      t=t+1;
+    }
+    
     if (!myFile) { /* open a new file */
       myDrive1.begin();
       myDrive1.startFilesystems();
@@ -352,11 +369,12 @@ void loop(void) {
       if (!myFiles1.begin(&myDrive1)) {
         if (DEBUG) Serial.print("initialization failed with code: ");
         if (DEBUG) myFiles1.printError(Serial);
+      } else {
+        i=next_file_number();  /* global access to myFiles1 */
+        sprintf(fname,"Log%04d.txt",i);
+        myFile = myFiles1.open(fname, FILE_WRITE);
+        myFile.println("Log Started "); // first line
       }
-      i=next_file_number();
-      sprintf(fname,"Log%04d.txt",i);
-      myFile = myFiles1.open(fname, FILE_WRITE);
-      myFile.println("Log Started "); // first line
     } /* open new file */
   } /* tick */
 }