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Arduino Sketch for senseBox:edu containing a webserver that displays data from a sd card.
WiFi Web Server Read SD Card
A simple web server that reads data from a SD card and displays
This example combines the following Arduino examples and is
for a senseBox:edu with WiFi and SDCard Bee.
#include <SPI.h>
#include <WiFi101.h>
#include <SD.h>
#include "SenseBoxMCU.h"
//#include "arduino_secrets.h"
///////please enter your sensitive data in the Secret tab/arduino_secrets.h
char ssid[] = "DEINE_SSID"; // your network SSID (name)
char pass[] = "DEIN_PASSWORD"; // your network password (use for WPA, or use as key for WEP)
int keyIndex = 0; // your network key Index number (needed only for WEP)
int status = WL_IDLE_STATUS;
WiFiServer server(80);
File myFile;
// Name der Datei auf der SD-Karte
// Achte darauf, dass dieser Name (ohne Dateiendung) nicht länger als 8 Buchstaben lang sein darf!
String fileName = "SenseBox.txt";
void setup() {
//Initialize serial and wait for port to open:
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
// check for the presence of the shield:
if (WiFi.status() == WL_NO_SHIELD) {
Serial.println("WiFi shield not present");
// don't continue:
while (true);
// attempt to connect to WiFi network:
while (status != WL_CONNECTED) {
Serial.print("Attempting to connect to SSID: ");
// Connect to WPA/WPA2 network. Change this line if using open or WEP network:
status = WiFi.begin(ssid, pass);
// wait 10 seconds for connection:
// you're connected now, so print out the status:
Serial.print("Initializing SD card...");
if (!SD.begin(28)) {
Serial.println("initialization failed!");
while (1);
Serial.println("initialization done.");
// open the file. note that only one file can be open at a time,
// so you have to close this one before opening another.
myFile =, FILE_WRITE);
// if the file opened okay, write to it:
if (myFile) {
Serial.print("Writing to test.txt...");
myFile.println("testing 1, 2, 3.");
// close the file:
} else {
// if the file didn't open, print an error:
Serial.println("error opening test.txt");
void loop() {
// listen for incoming clients
WiFiClient client = server.available();
if (client) {
Serial.println("new client");
// an http request ends with a blank line
bool currentLineIsBlank = true;
while (client.connected()) {
if (client.available()) {
char c =;
// if you've gotten to the end of the line (received a newline
// character) and the line is blank, the http request has ended,
// so you can send a reply
if (c == '\n' && currentLineIsBlank) {
// send a standard http response header
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println("Connection: close"); // the connection will be closed after completion of the response
client.println("Refresh: 5"); // refresh the page automatically every 5 sec
client.println("<!DOCTYPE HTML>");
// output the value of each analog input pin
myFile =;
if (myFile) {
while (myFile.available()) {
client.println("<br />");
} else {
client.print("error opening file from SD Card");
if (c == '\n') {
// you're starting a new line
currentLineIsBlank = true;
else if (c != '\r') {
// you've gotten a character on the current line
currentLineIsBlank = false;
// give the web browser time to receive the data
// close the connection:
Serial.println("client disconnected");
void printWiFiStatus() {
// print the SSID of the network you're attached to:
Serial.print("SSID: ");
// print your WiFi shield's IP address:
IPAddress ip = WiFi.localIP();
Serial.print("IP Address: ");
// print the received signal strength:
long rssi = WiFi.RSSI();
Serial.print("signal strength (RSSI):");
Serial.println(" dBm");
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