I wonder if someone could point me in the right direction.
I'm trying to get the example sketch, BlinkLED, working using the TinyWebServer library.
It all compiles nicely, but at runtime it appears to fail when it gets to any file.open commands. It's using the Sd2Card, SdVolume and SdFile classes, and I wonder if something has changed in those libraries since the original example was written to stop things working?
I'm pretty sure everything is correct hardware-wise as I can use the documented SD.h classes to read and write from the SD card.
Unfortunately, I'm very new to arduino and don't have the skills to migrate the BlinkLED example to use SD rather than SdFile.
Has anyone got any experience with this?
Help! 
Here's the code I am running
// -*- c++ -*-
//
// Copyright 2010 Ovidiu Predescu <ovidiu@gmail.com>
// Date: December 2010
// Updated: 08-JAN-2012 for Arduno IDE 1.0 by <Hardcore@hardcoreforensics.com>
//
#include <pins_arduino.h>
#include <SPI.h>
#include <Ethernet.h>
#include <Flash.h>
#include <SD.h>
#include <TinyWebServer.h>
/****************VALUES YOU CHANGE*************/
// The LED attached to PIN X on an Arduino board.
const int LEDPIN = 7;
// pin 4 is the SPI select pin for the SDcard
const int SD_CS = 4;
// pin 10 is the SPI select pin for the Ethernet
const int ETHER_CS = 10;
// Don't forget to modify the IP to an available one on your home network
byte ip[] = { 192, 168, 0, 160 };
/*********************************************/
static uint8_t mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
// The initial state of the LED
int ledState = LOW;
void setLedEnabled(boolean state) {
ledState = state;
digitalWrite(LEDPIN, ledState);
}
inline boolean getLedState() { return ledState; }
boolean file_handler(TinyWebServer& web_server);
boolean blink_led_handler(TinyWebServer& web_server);
boolean led_status_handler(TinyWebServer& web_server);
boolean index_handler(TinyWebServer& web_server);
TinyWebServer::PathHandler handlers[] = {
// Work around Arduino's IDE preprocessor bug in handling /* inside
// strings.
//
// `put_handler' is defined in TinyWebServer
{"/", TinyWebServer::GET, &index_handler },
{"/upload/" "*", TinyWebServer::PUT, &TinyWebPutHandler::put_handler },
{"/blinkled", TinyWebServer::POST, &blink_led_handler },
{"/ledstatus" "*", TinyWebServer::GET, &led_status_handler },
{"/" "*", TinyWebServer::GET, &file_handler },
{NULL},
};
const char* headers[] = {
"Content-Length",
NULL
};
TinyWebServer web = TinyWebServer(handlers, headers);
boolean has_filesystem = true;
Sd2Card card;
SdVolume volume;
SdFile root;
SdFile file;
void send_file_name(TinyWebServer& web_server, const char* filename) {
if (!filename) {
web_server.send_error_code(404);
web_server << F("Could not parse URL");
} else {
TinyWebServer::MimeType mime_type
= TinyWebServer::get_mime_type_from_filename(filename);
web_server.send_error_code(200);
web_server.send_content_type(mime_type);
web_server.end_headers();
if (file.open(&root, filename, O_READ)) {
Serial << F("Read file "); Serial.println(filename);
web_server.send_file(file);
file.close();
} else {
web_server << F("Could not find file: ") << filename << "\n";
}
}
}
boolean file_handler(TinyWebServer& web_server) {
char* filename = TinyWebServer::get_file_from_path(web_server.get_path());
send_file_name(web_server, filename);
free(filename);
return true;
}
boolean blink_led_handler(TinyWebServer& web_server) {
web_server.send_error_code(200);
web_server.send_content_type("text/plain");
web_server.end_headers();
// Reverse the state of the LED.
setLedEnabled(!getLedState());
Client& client = web_server.get_client();
if (client.available()) {
char ch = (char)client.read();
if (ch == '0') {
setLedEnabled(false);
} else if (ch == '1') {
setLedEnabled(true);
}
}
return true;
}
boolean led_status_handler(TinyWebServer& web_server) {
web_server.send_error_code(200);
web_server.send_content_type("text/plain");
web_server.end_headers();
Client& client = web_server.get_client();
client.println(getLedState(), DEC);
return true;
}
boolean index_handler(TinyWebServer& web_server) {
send_file_name(web_server, "INDEX.HTM");
return true;
}
void file_uploader_handler(TinyWebServer& web_server,
TinyWebPutHandler::PutAction action,
char* buffer, int size) {
static uint32_t start_time;
static uint32_t total_size;
switch (action) {
case TinyWebPutHandler::START:
start_time = millis();
total_size = 0;
if (!file.isOpen()) {
// File is not opened, create it. First obtain the desired name
// from the request path.
char* fname = web_server.get_file_from_path(web_server.get_path());
if (fname) {
Serial << F("Creating ") << fname << "\n";
file.open(&root, fname, O_CREAT | O_WRITE | O_TRUNC);
free(fname);
}
}
break;
case TinyWebPutHandler::WRITE:
if (file.isOpen()) {
file.write(buffer, size);
total_size += size;
}
break;
case TinyWebPutHandler::END:
file.sync();
Serial << F("Wrote ") << file.fileSize() << F(" bytes in ")
<< millis() - start_time << F(" millis (received ")
<< total_size << F(" bytes)\n");
file.close();
}
}
void setup() {
Serial.begin(115200);
Serial << F("Free RAM: ") << FreeRam() << "\n";
pinMode(LEDPIN, OUTPUT);
setLedEnabled(false);
pinMode(SS_PIN, OUTPUT); // set the SS pin as an output
// (necessary to keep the board as
// master and not SPI slave)
digitalWrite(SS_PIN, HIGH); // and ensure SS is high
// Ensure we are in a consistent state after power-up or a reset
// button These pins are standard for the Arduino w5100 Rev 3
// ethernet board They may need to be re-jigged for different boards
pinMode(ETHER_CS, OUTPUT); // Set the CS pin as an output
digitalWrite(ETHER_CS, HIGH); // Turn off the W5100 chip! (wait for
// configuration)
pinMode(SD_CS, OUTPUT); // Set the SDcard CS pin as an output
digitalWrite(SD_CS, HIGH); // Turn off the SD card! (wait for
// configuration)
// initialize the SD card.
Serial << F("Setting up SD card...\n");
// Pass over the speed and Chip select for the SD card
if (!card.init(SPI_FULL_SPEED, SD_CS)) {
Serial << F("card failed\n");
has_filesystem = false;
}
// initialize a FAT volume.
if (!volume.init(&card)) {
Serial << F("vol.init failed!\n");
has_filesystem = false;
}
if (!root.openRoot(&volume)) {
Serial << F("openRoot failed");
has_filesystem = false;
}
if (has_filesystem) {
// Assign our function to `upload_handler_fn'.
TinyWebPutHandler::put_handler_fn = file_uploader_handler;
}
// Initialize the Ethernet.
Serial << F("Setting up the Ethernet card...\n");
Ethernet.begin(mac, ip);
// Start the web server.
Serial << F("Web server starting...\n");
web.begin();
Serial << F("Ready to accept HTTP requests.\n");
}
void loop() {
if (has_filesystem) {
web.process();
}
}
