#include <MKRGSM.h>

#include <SSU.h>

constexpr char UPDATE_FILE_NAME[] = "UPDATE.BIN";

static constexpr char CHECK_FILE_NAME[] = "UPDATE.OK";

#include "arduino_secrets.h"

const char PINNUMBER[] = SECRET_PINNUMBER;

const char GPRS_APN[] = SECRET_GPRS_APN;

const char GPRS_LOGIN[] = SECRET_GPRS_LOGIN;

const char GPRS_PASSWORD[] = SECRET_GPRS_PASSWORD;

GSMSSLClient client;

GPRS gprs;

GSM gsmAccess;

GSMFileUtils fileUtils;

bool isHeaderComplete = false;

String httpHeader;

bool isDownloadComplete = false;

unsigned int fileSize = 0;

unsigned int totalWritten = 0;

constexpr char server[] = "example.org";

constexpr int port = 443;

constexpr char filename[] = "update.bin";

void setup()

{

unsigned long timeout = millis();

Serial.begin(9600);

while (!Serial && millis() - timeout < 5000)

;

Serial.println("Starting OTA Update via HTTP and Arduino SSU.");

Serial.println();

bool connected = false;

Serial.print("Connecting to cellular network... ");

while (!connected) {

if ((gsmAccess.begin(PINNUMBER) == GSM_READY) && (gprs.attachGPRS(GPRS_APN, GPRS_LOGIN, GPRS_PASSWORD) == GPRS_READY)) {

connected = true;

} else {

Serial.println("Not connected");

delay(1000);

}

}

Serial.println("Connected.");

Serial.println();

// Modem has already been initialized in the sketch:

// begin FileUtils without MODEM initialization.

fileUtils.begin(false);

Serial.print("Connecting to ");

Serial.print(server);

Serial.print(":");

Serial.print(port);

Serial.print("... ");

if (client.connect(server, port)) {

Serial.println("Connected.");

Serial.print("Downloading ");

Serial.println(filename);

Serial.print("... ");

// Make the HTTP request:

client.print("GET /");

client.print(filename);

client.println(" HTTP/1.1");

client.print("Host: ");

client.println(server);

client.println("Connection: close");

client.println();

} else {

Serial.println("Connection failed");

}

}

void loop()

{

while (client.available()) {

// Skip the HTTP header

if (!isHeaderComplete) {

const char c = client.read();

httpHeader += c;

if (httpHeader.endsWith("\r\n\r\n")) {

isHeaderComplete = true;

// Get the size of the OTA file from the

// HTTP Content-Length header.

fileSize = getContentLength();

Serial.println();

Serial.print("HTTP header complete. ");

Serial.print("OTA file size is ");

Serial.print(fileSize);

Serial.println(" bytes.");

if (fileSize == 0) {

Serial.println("Unable to get OTA file size.");

while (true)

;

}

}

} else {

// Read the OTA file in len-bytes blocks to preserve RAM.

constexpr size_t len { 512 };

char buf[len] { 0 };

// Read len bytes from HTTP client...

uint32_t read = client.readBytes(buf, len);

// and append them to the update file.

uint32_t written = fileUtils.appendFile(UPDATE_FILE_NAME, buf, read);

if (written != read) {

Serial.println("Error while saving data.");

while (true)

;

}

// Update the received byte counter

totalWritten += written;

// Check for full file received and stored

isDownloadComplete = totalWritten == fileSize;

Serial.print("Received: ");

Serial.print(totalWritten);

Serial.print("/");

Serial.println(fileSize);

}

}

if (isDownloadComplete) {

Serial.println();

Serial.println("Download complete.");

Serial.println("Enabling checkpoint.");

Serial.println();

// Create the checkpoint file: will be removed by SSU

// after successful update.

auto status = fileUtils.downloadFile(CHECK_FILE_NAME, { 0 }, 1);

if (status != 1) {

Serial.println("Unable to create checkpoint file.");

while (true)

;

}

Serial.println("Resetting MCU in order to trigger SSU...");

Serial.println();

delay(500);

NVIC_SystemReset();

}

}

int getContentLength()

{

const String contentLengthHeader = "Content-Length:";

const auto contentLengthHeaderLen = contentLengthHeader.length();

auto indexContentLengthStart = httpHeader.indexOf(contentLengthHeader);

if (indexContentLengthStart < 0) {

Serial.println("Unable to find Content-Length header (Start)");

return 0;

}

auto indexContentLengthStop = httpHeader.indexOf("\r\n", indexContentLengthStart);

if (indexContentLengthStart < 0) {

Serial.println("Unable to find Content-Length header (Stop)");

return 0;

}

auto contentLength = httpHeader.substring(indexContentLengthStart + contentLengthHeaderLen + 1, indexContentLengthStop);

contentLength.trim();

return contentLength.toInt();

}

#define SECRET_PINNUMBER ""

#define SECRET_GPRS_APN "GPRS_APN" // replace your GPRS APN

#define SECRET_GPRS_LOGIN "login" // replace with your GPRS login

#define SECRET_GPRS_PASSWORD "password" // replace with your GPRS password

#include <MKRGSM.h>

static char const BINARY[] =

{

#include "Binary.h"

};

GSMFileUtils fileUtils;

void setup() {

Serial.begin(9600);

unsigned long const start = millis();

for(unsigned long now = millis(); !Serial && ((now - start) < 5000); now = millis()) { };

Serial.print("Accessing SARA U-201 Filesystem... ");

if(!fileUtils.begin()) {

Serial.println("failed.");

return;

}

Serial.println("OK");

Serial.print("Writing \"UPDATE.BIN\" ... ");

uint32_t bytes_to_write = sizeof(BINARY);

auto bytes_written = fileUtils.downloadFile("UPDATE.BIN", BINARY, bytes_to_write);

if(bytes_written != bytes_to_write) {

Serial.println("downloadFile failed.");return;

} else {

Serial.print("OK (");

Serial.print(bytes_written);

Serial.println(" bytes written)");

}

}

void loop() {

}

#include <SSU.h>

void setup()

{

Serial.begin(9600);

while (!Serial) { }

// wait a bit

delay(1000);

String message;

message += "Sketch compile date and time: ";

message += __DATE__;

message += " ";

message += __TIME__;

// print out the sketch compile date and time on the serial port

Serial.println(message);

}

void loop()

{

// add you own code here

}