microSD card writing is now functional. Hooray :D

iot/main/main.ino

@@ -36,16 +36,13 @@ void setup() {
 	
 	peripheral_unsilence(PIN_SPI_CS_SD);
 	
-	store_init();
 	Serial.println(freeMemory(), DEC);
 	store_reading(id, gps_data);
 	Serial.println(freeMemory(), DEC);
 	#ifdef SD_DEBUG_ENABLED
-	store_debug(gps_data.time, 19);
-	#endif
-	Serial.println(freeMemory(), DEC);
-	store_end();
+	store_debug(gps_data.time, 19 - 1); // Don't print the null byte
 	Serial.println(freeMemory(), DEC);
+	#endif
 	
 	// ------------------------------------------------------------------------
 	

iot/main/storage.cpp

@@ -5,44 +5,44 @@
 #include "settings.h"
 #include "gps.h"
 
-// FUTURE: We might be able to trim it down if we disable long filenames with #define USE_LONG_FILE_NAMES 0
-SdFat* card = nullptr;
+// FUTURE: We might be able to trim it down if we disable long filenames with #define 
 
-void store_init() {
-	card = new SdFat();
-	if(!card->begin(PIN_SPI_CS_SD)) {
+SdFat store_init() {
+	SdFat card;
+	if(!card.begin(PIN_SPI_CS_SD)) {
 		Serial.println("Error: MicroSD card init failed");
 		while(true) delay(100);
 	}
+	return card;
 }
 
 void store_reading(uint32_t id, GPSLocation location) {
 	// Port the rest of this to SdFat from SD
+	SdFat card = store_init();
 	
 	// Open the file to  write the data to. If it doesn't exist it will be created.
 	// Unlike elsewhere, FILE_WRITE opens the file with the cursor starting at the end, so it's basically actually equivalent to FILE_APPEND that we use in other environments. Confusing, I know.
-	File handle = card->open(SD_FILENAME, O_APPEND | O_CREAT | O_WRONLY);
-	
-	char line[33];
-	int chars = snprintf(line, 33, "%d\t%06d\t%06d\n",
-		id,
-		location.lat, location.lng
-	);
-	handle.write(line, chars);
-	
+	File handle = card.open(SD_FILENAME, O_APPEND | O_CREAT | O_WRONLY);
+	uint8_t places = 6;
+	handle.printField(id, '\t');
+	handle.printField(location.lat, '\t', places);
+	handle.printField(location.lng, '\n', places);
 	handle.close(); // Syncs implicitly
 }
 
 void store_debug(char* buffer, int size) {
-	File handle = card->open(SD_FILENAME_DEBUG, O_APPEND | O_CREAT | O_WRONLY);
+	SdFat card = store_init();
+	File handle = card.open(SD_FILENAME_DEBUG, O_APPEND | O_CREAT | O_WRONLY);
 	handle.write(buffer, size);
 	handle.write('\n');
 	handle.close();
 }
 
+/*
 void store_end() {
 	// Apparently we'ree fine so long as we don't have any open file handles - there's no end() method on the SdFat class
 	// card->end();
 	delete card;
 	card = nullptr;
 }
+*/

iot/main/storage.h

@@ -11,4 +11,4 @@ void store_reading(uint32_t id, GPSLocation location);
 
 void store_debug(char* buffer, int size);
 
-void store_end();
+// void store_end();