trunk/Arduino/libraries/SD/examples/listfiles/listfiles.ino

@@ -1,15 +1,18 @@
 /*
   Listfiles
 
-  This example shows how print out the files in a
-  directory on a SD card
+  This example shows how to print out the files in a
+  directory on a SD card. Pin numbers reflect the default
+  SPI pins for Uno and Nano models
 
   The circuit:
    SD card attached to SPI bus as follows:
- ** MOSI - pin 11
- ** MISO - pin 12
+ ** SDO - pin 11
+ ** SDI - pin 12
  ** CLK - pin 13
- ** CS - pin 4 (for MKRZero SD: SDCARD_SS_PIN)
+ ** CS - depends on your SD card shield or module.
+ 		Pin 10 used here for consistency with other Arduino examples
+    (for MKR Zero SD: SDCARD_SS_PIN)
 
   created   Nov 2010
   by David A. Mellis
@@ -17,28 +20,34 @@
   by Tom Igoe
   modified 2 Feb 2014
   by Scott Fitzgerald
-
+  modified 24 July 2020
+  by Tom Igoe
+  
   This example code is in the public domain.
 
 */
-#include <SPI.h>
 #include <SD.h>
 
+const int chipSelect = 10;
 File root;
 
 void setup() {
-  // Open serial communications and wait for port to open:
+ // Open serial communications and wait for port to open:
   Serial.begin(9600);
-  while (!Serial) {
-    ; // wait for serial port to connect. Needed for native USB port only
-  }
+  // wait for Serial Monitor to connect. Needed for native USB port boards only:
+  while (!Serial);
 
   Serial.print("Initializing SD card...");
 
-  if (!SD.begin(4)) {
-    Serial.println("initialization failed!");
-    while (1);
+  if (!SD.begin(chipSelect)) {
+    Serial.println("initialization failed. Things to check:");
+    Serial.println("1. is a card inserted?");
+    Serial.println("2. is your wiring correct?");
+    Serial.println("3. did you change the chipSelect pin to match your shield or module?");
+    Serial.println("Note: press reset button on the board and reopen this Serial Monitor after fixing your issue!");
+    while (true);
   }
+
   Serial.println("initialization done.");
 
   root = SD.open("/");
@@ -75,6 +84,3 @@ void printDirectory(File dir, int numTabs) {
     entry.close();
   }
 }
-
-
-