First Commit

libraries/SdFat/examples/examplesV1/ReadCsvArray/ReadCsvArray.ino

@@ -0,0 +1,139 @@
+// Read a two dimensional array from a CSV file.
+//
+#include <SPI.h>
+#include <SdFat.h>
+#define CS_PIN SS
+
+// 5 X 4 array
+#define ROW_DIM 5
+#define COL_DIM 4
+
+SdFat SD;
+File file;
+
+/*
+ * Read a file one field at a time.
+ *
+ * file - File to read.
+ *
+ * str - Character array for the field.
+ *
+ * size - Size of str array.
+ *
+ * delim - String containing field delimiters.
+ *
+ * return - length of field including terminating delimiter.
+ *
+ * Note, the last character of str will not be a delimiter if
+ * a read error occurs, the field is too long, or the file
+ * does not end with a delimiter.  Consider this an error
+ * if not at end-of-file.
+ *
+ */
+size_t readField(File* file, char* str, size_t size, const char* delim) {
+  char ch;
+  size_t n = 0;
+  while ((n + 1) < size && file->read(&ch, 1) == 1) {
+    // Delete CR.
+    if (ch == '\r') {
+      continue;
+    }
+    str[n++] = ch;
+    if (strchr(delim, ch)) {
+        break;
+    }
+  }
+  str[n] = '\0';
+  return n;
+}
+//------------------------------------------------------------------------------
+#define errorHalt(msg) {Serial.println(F(msg)); while (true) {}}
+//------------------------------------------------------------------------------
+void setup() {
+  Serial.begin(9600);
+
+  // Wait for USB Serial
+  while (!Serial) {
+    yield();
+  }
+  Serial.println("Type any character to start");
+  while (!Serial.available()) {
+    yield();
+  }
+  // Initialize the SD.
+  if (!SD.begin(CS_PIN)) {
+    errorHalt("begin failed");
+  }
+  // Create or open the file.
+  file = SD.open("READNUM.TXT", FILE_WRITE);
+  if (!file) {
+    errorHalt("open failed");
+  }
+  // Rewind file so test data is not appended.
+  file.rewind();
+
+  // Write test data.
+  file.print(F(
+    "11,12,13,14\r\n"
+    "21,22,23,24\r\n"
+    "31,32,33,34\r\n"
+    "41,42,43,44\r\n"
+    "51,52,53,54"     // Allow missing endl at eof.
+    ));
+
+  // Rewind the file for read.
+  file.rewind();
+
+  // Array for data.
+  int array[ROW_DIM][COL_DIM];
+  int i = 0;     // First array index.
+  int j = 0;     // Second array index
+  size_t n;      // Length of returned field with delimiter.
+  char str[20];  // Must hold longest field with delimiter and zero byte.
+  char *ptr;     // Test for valid field.
+
+  // Read the file and store the data.
+
+  for (i = 0; i < ROW_DIM; i++) {
+    for (j = 0; j < COL_DIM; j++) {
+      n = readField(&file, str, sizeof(str), ",\n");
+      if (n == 0) {
+        errorHalt("Too few lines");
+      }
+      array[i][j] = strtol(str, &ptr, 10);
+      if (ptr == str) {
+        errorHalt("bad number");
+      }
+      while (*ptr == ' ') {
+        ptr++;
+      }
+      if (*ptr != ',' && *ptr != '\n' && *ptr != '\0') {
+        errorHalt("extra characters in field");
+      }
+      if (j < (COL_DIM-1) && str[n-1] != ',') {
+        errorHalt("line with too few fields");
+      }
+    }
+    // Allow missing endl at eof.
+    if (str[n-1] != '\n' && file.available()) {
+      errorHalt("missing endl");
+    }
+  }
+
+  // Print the array.
+  for (i = 0; i < ROW_DIM; i++) {
+    for (j = 0; j < COL_DIM; j++) {
+      if (j) {
+        Serial.print(' ');
+      }
+      Serial.print(array[i][j]);
+    }
+    Serial.println();
+  }
+  Serial.println("Done");
+  file.close();
+}
+//------------------------------------------------------------------------------
+void loop() {
+}
+