I plan to send from a server a POST request to my Arduino Uno WiFi Rev2. More correctly, when the server sends this request a servomotor controlled by the Arduino should start moving. Right now, I'm using Postman to try and connect with the Arduino but I can't get it to work. So first I connect the Arduino to WiFi using my smartphone as a hotspot. This should be the unit's IP address, right?
I then try to send a POST request to this IP but it doesn't work. I'm also unsure which port number I should use, so I have just been trying with the standard ones (80, 4430, etc).
What am I doing wrong and how should I proceed?
EDIT: Here is my code.
#include <SPI.h>
#include <Servo.h>
#include <WiFiNINA.h>
char ssid[] = "MyNetwork"; // The network SSID
char pass[] = "testtest"; // The network password
int status = WL_IDLE_STATUS; // The Wifi radio's connection status
Servo servo_9; // Initializes the servomotor
WiFiServer server(80); // Server socket
//WiFiClient client;
WiFiClient client = server.available();
void setup() {
// Connects the servomotor to pin 9
servo_9.attach(9, 500, 2500);
// Initialize serial and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // Wait for serial port to connect. Needed for native USB port only
}
enable_WiFi();
connect_WiFi();
server.begin();
printCurrentNet();
printWifiData();
}
void loop() {
// Check the network connection once every 10 seconds:
delay(10000);
client = server.available();
if(client){
printWEB();
}
}
void enable_WiFi(){
// Check for the WiFi module:
if (WiFi.status() == WL_NO_MODULE) {
Serial.println("Communication with WiFi module failed!");
// Don't continue
while (true);
}
// Check if the latest Firmware version is installed
String fv = WiFi.firmwareVersion();
if (fv < WIFI_FIRMWARE_LATEST_VERSION) {
Serial.println("Please upgrade the firmware");
}
}
void connect_WiFi(){
// Attempt to connect to Wifi network:
while (status != WL_CONNECTED) {
Serial.print("Attempting to connect to WPA SSID: ");
Serial.println(ssid);
// Connect to WPA/WPA2 network:
status = WiFi.begin(ssid, pass);
// Wait 10 seconds for connection:
delay(10000);
}
// Now the arduino is connected, so print out the data:
Serial.print("You're connected to the network: ");
Serial.println();
}
void printCurrentNet() {
// Print the SSID of the network you're attached to:
Serial.print("SSID: ");
Serial.println(WiFi.SSID());
// Print the MAC address of the router you're attached to:
byte bssid[6];
WiFi.BSSID(bssid);
Serial.print("BSSID: ");
printMacAddress(bssid);
// Print the received signal strength:
long rssi = WiFi.RSSI();
Serial.print("Signal strength (RSSI): ");
Serial.println(rssi);
// Print the encryption type:
byte encryption = WiFi.encryptionType();
Serial.print("Encryption Type: ");
Serial.println(encryption, HEX);
Serial.println();
}
void printWifiData() {
Serial.println("Your board's IP and MAC address: ");
// Print your board's IP address:
IPAddress ip = WiFi.localIP();
Serial.print("IP Address: ");
Serial.println(ip);
// Print your MAC address:
byte mac[6];
WiFi.macAddress(mac);
Serial.print("MAC address: ");
printMacAddress(mac);
Serial.println();
}
// Find the MAC adress for your Arduino board
void printMacAddress(byte mac[]) {
for (int i = 5; i >= 0; i--) {
if (mac[i] < 16) {
Serial.print("0");
}
Serial.print(mac[i], HEX);
if (i > 0) {
Serial.print(":");
}
}
Serial.println();
}
void printWEB() {
if (client) { // if you get a client,
Serial.println("new client"); // print a message out the serial port
String currentLine = ""; // make a String to hold incoming data from the client
while (client.connected()) { // loop while the client's connected
if (client.available()) { // if there's bytes to read from the client,
char c = client.read(); // read a byte, then
Serial.write(c); // print it out the serial monitor
if (c == '\n') { // if the byte is a newline character
// if the current line is blank, you got two newline characters in a row.
// that's the end of the client HTTP request, so send a response:
if (currentLine.length() == 0) {
// HTTP headers always start with a response code (e.g. HTTP/1.1 200 OK)
// and a content-type so the client knows what's coming, then a blank line:
client.println("HTTP/1.1 200 OK");
client.println("Content-type:text/html");
client.println();
// The HTTP response ends with another blank line:
client.println();
// break out of the while loop:
break;
}
else { // if you got a newline, then clear currentLine:
currentLine = "";
}
}
else if (c != '\r') { // if you got anything else but a carriage return character,
currentLine += c; // add it to the end of the currentLine
}
}
}
// close the connection:
client.stop();
Serial.println("client disconnected");
}
}
void servomotorGate(){
int position = 0;
for (position = 0; position <= 90; position += 1) {
servo_9.write(position);
Serial.println("Opening the gate");
}
delay(5000); // Wait for 5000 millisecond(s)
for (position = 90; position >= 0; position -= 1) {
servo_9.write(position);
Serial.println("Closing the gate");
}
}
I added the server client to listen for connections. However, the main reason why I couldn't connect to my IP address with Postman was that I was trying to get WiFi from my phone as a hotspot. I guess there is a problem with the port forwarding when using a hotspot. In the end, I solved the issue by connecting to a normal router WiFi network.
I'm working on a project that includes working with arduino hardware remotely. I would like to learn how to create a simple script that allows me to turn on and off the Led builtin to my MKR1000 wirelessly. I could then use this knowledge in more complicated projects. After doing some research and looking at the arduino library's sample webserver program, I came up with this Frankenstein of code. After working for hours I just keep on making it worse, I could really use some guidance on what I'm doing wrong, why and how to fix it.
My Frankenstein code:
#include <WiFi101.h>
#include <SPI.h>
char ssid[] = "ARROW_015D80";
char pass[] = "KRR3K47XZXM3NYRHV7GX";
int status = WL_IDLE_STATUS;
int LED = LED_BUILTIN;
int LEDState = digitalRead(LED);
WiFiServer server(80);
void setup() {
while (!Serial) {
}
Serial.begin(9600);
if (WiFi.status() == WL_NO_SHIELD) {
Serial.println("Yo, where the wifi shield at?");
while(true);
}
while (status !=WL_CONNECTED) {
Serial.print("Connecting to ssid: ");
Serial.println(ssid);
status = WiFi.begin(ssid, pass);
delay(10000);
}
server.begin();
printWiFiStatus();
}
void loop() {
WiFiClient client = server.available();
if (client) {
Serial.println("+1 Client");
String currentLine = "";
while (client.connected()) {
if (client.available()) {
char c = client.read();
Serial.write(c);
if (c == '\n') {
if(currentLine.length() == 0) {
client.println("HTTP/1.1 200 OK");
client.println("Content-Type: text/html");
client.println();
client.println("Refresh: 1"); // refresh the page automatically every 5 sec
client.println();
client.println("<!DOCTYPE HTML>");
client.println("<html>");
client.print("State of button:");
if (LEDState == HIGH){
client.print("ON");
}
if (LEDState == LOW){
client.print("OFF");
}
client.println("<br>");
client.println("</html>");
client.println();
break;
}
else {
currentLine = "";
}
}
else if (c !='\r') {
currentLine += c;
}
if (currentLine.endsWith("GET /H")) {
digitalWrite(LED, HIGH);
}
if (currentLine.endsWith("Get /L")) {
digitalWrite(LED, LOW);
}
if (currentLine.endsWith("Get /stop")){
client.stop();
Serial.println ("Client disconnected");
}
}
}
}
}
void printWiFiStatus() {
Serial.print("SSID: ");
Serial.println(WiFi.SSID());
IPAddress ip = WiFi.localIP();
Serial.print("IP Address: ");
Serial.println(ip);
long rssi = WiFi.RSSI();
Serial.print("signal strength (RSSI):");
Serial.print(rssi);
Serial.println(" dBm");
}
According to the videos and the mismatch of information, this program should connect the arduino to the internet, print the arduino's ip address in the serial monitor and I should be able to change the state of the built in LED by changing the end of the ip address search.
Instead, after showing the ip address and displaying the page, with the button state on it. When I try to change the url to change the button state it bugs out. It takes me to the "This page can't be reached" and the serialmonitor bug out.
Never mind, I found a video online that explain clearly how to write the code I'm looking for. It is extremely helpful : https://www.youtube.com/watch?v=H0p7GVPdlyU
It also link to a page with all the code for it.
I am using SIM 900 GSM module, and I am using this code for GSM based data connection. But problem is I am not getting any feedback from my code. I am from Bangladesh, using a local sim provider's SIM card(Grameen Phone(Telenor)). It's APN is gpinternet/gpwap. But what is the username & password. If the module can connect then it will show some positive feedback otherwise negative. but it showing nothing. Where is my problem? can anyone help me.
#include <GSM.h>
#define PINNUMBER "1234"
// APN data
#define GPRS_APN "gpinternet" // replace your GPRS APN
#define GPRS_LOGIN "" // replace with your GPRS login
#define GPRS_PASSWORD "" // replace with your GPRS password
// initialize the library instance
GPRS gprs;
GSM gsmAccess; // include a 'true' parameter for debug enabled
GSMServer server(80); // port 80 (http default)
// timeout
const unsigned long __TIMEOUT__ = 10 * 100;
void setup() {
// initialize 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
}
// connection state
boolean notConnected = true;
// Start GSM shield
// If your SIM has PIN, pass it as a parameter of begin() in quotes
while (notConnected) {
if ((gsmAccess.begin(PINNUMBER) == GSM_READY) & (gprs.attachGPRS(GPRS_APN, GPRS_LOGIN, GPRS_PASSWORD) == GPRS_READY)) {
notConnected = false;
} else {
Serial.println("Not connected");
delay(1000);
}
}
Serial.println("Connected to GPRS network");
// start server
server.begin();
//Get IP.
IPAddress LocalIP = gprs.getIPAddress();
Serial.println("Server IP address=");
Serial.println(LocalIP);
}
void loop() {
// listen for incoming clients
GSMClient client = server.available();
if (client) {
while (client.connected()) {
if (client.available()) {
Serial.println("Receiving request!");
bool sendResponse = false;
while (char c = client.read()) {
if (c == '\n') {
sendResponse = true;
}
}
// if you've gotten to the end of the line (received a newline
// character)
if (sendResponse) {
Serial.println("HI man");
}
}
}
}
}
I can't connect and I don't know why, can somebody help me?
The console returns:
"/tmp/arduino_ca13faa5535f759e3ad5c18bb4094ecd/SendSMS.ino: In function 'void setup()':
/tmp/arduino_ca13faa5535f759e3ad5c18bb4094ecd/SendSMS.ino:48:34: warning: deprecated conversion from string constant to 'char*' [-Wwrite-strings]
if (gsmAccess.begin(PINNUMBER) == GSM_READY) { "
#include <GSM.h>
#define PINNUMBER ""
// initialize the library instance
GSM gsmAccess;
GSM_SMS sms;
void setup() {
// initialize 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
}
Serial.println("SMS Messages Sender");
// connection state
boolean notConnected = true;
// Start GSM shield
// If your SIM has PIN, pass it as a parameter of begin() in quotes
while (notConnected) {
if (gsmAccess.begin(PINNUMBER) == GSM_READY) {
notConnected = false;
} else {
Serial.println("Not connected");
delay(1000);
}
}
Serial.println("GSM initialized");
}
void loop() {
Serial.print("Enter a mobile number: ");
char remoteNum[20]; // telephone number to send sms
readSerial(remoteNum);
Serial.println(remoteNum);
// sms text
Serial.print("Now, enter SMS content: ");
char txtMsg[200];
readSerial(txtMsg);
Serial.println("SENDING");
Serial.println();
Serial.println("Message:");
Serial.println(txtMsg);
// send the message
sms.beginSMS(remoteNum);
sms.print(txtMsg);
sms.endSMS();
Serial.println("\nCOMPLETE!\n");
}
/*
Read input serial
*/
int readSerial(char result[]) {
int i = 0;
while (1) {
while (Serial.available() > 0) {
char inChar = Serial.read();
if (inChar == '\n') {
result[i] = '\0';
Serial.flush();
return 0;
}
if (inChar != '\r') {
result[i] = inChar;
i++;
}
}
}
}
That's just a warning. The sketch is building fine. What do you see on the Serial Monitor window? (drag-select, copy and paste into a comment below.)
You haven't set the PIN to anything, like "1234". Do you have a PIN?
#include <SoftwareSerial.h>
char inchar; //Will hold the incoming character from the serial port.
SoftwareSerial cell(2,3); //Create a 'fake' serial port. Pin 2 is the Rx pin, pin 3 is the Tx pin.
int led1 = A2;
void setup()
{
// Prepare the digital output pins
pinMode(led1, OUTPUT);
digitalWrite(led1, HIGH);
//Initialize GSM module serial port for communication.
cell.begin(19200);
delay(30000); // Give time for GSM module to register on network, etc.
cell.println("AT+CMGF=1"); // Set SMS mode to text
delay(200);
cell.println("AT+CNMI=3,3,0,0"); // Set module to send SMS data to serial out upon receipt
delay(200);
}
void loop()
{
//If a character comes in from the cellular module...
if(cell.available() >0)
{
delay(10);
inchar=cell.read();
if (inchar=='a')
{
delay(10);
inchar=cell.read();
if (inchar=='0')
{
digitalWrite(led1, LOW);
}
else if (inchar=='1')
{
digitalWrite(led1, HIGH);
}
delay(10);
delay(10);
}
cell.println("AT+CMGD=1,4"); // Delete all SMS
}
}
This is the code for receiving SMSes from the cellular network. I am using the Arduino Gboard with SIM900. There is no error in the code, but the LED on the board doesn't switch on or off in response to an SMS.
Why?
Here's a fully functional code for sending a command thru SMS using Arduino and GSM, it will also reply the state of the light.
#include <SoftwareSerial.h>
SoftwareSerial GPRS(10, 11);
String textMessage;
String lampState;
const int relay = 12; //If you're using a relay to switch, if not reverse all HIGH and LOW on the code
void setup() {
pinMode(relay, OUTPUT);
digitalWrite(relay, HIGH); // The current state of the light is ON
Serial.begin(9600);
GPRS.begin(9600);
delay(5000);
Serial.print("GPRS ready...\r\n");
GPRS.print("AT+CMGF=1\r\n");
delay(1000);
GPRS.print("AT+CNMI=2,2,0,0,0\r\n");
delay(1000);
}
void loop(){
if(GPRS.available()>0){
textMessage = GPRS.readString();
Serial.print(textMessage);
delay(10);
}
if(textMessage.indexOf("ON")>=0){ //If you sent "ON" the lights will turn on
// Turn on relay and save current state
digitalWrite(relay, HIGH);
lampState = "ON";
Serial.println("Lamp set to ON\r\n");
textMessage = "";
GPRS.println("AT+CMGS=\"+631234567890\""); // RECEIVER: change the phone number here with international code
delay(500);
GPRS.print("Lamp was finally switched ON.\r");
GPRS.write( 0x1a );
delay(1000);
}
if(textMessage.indexOf("OFF")>=0){
// Turn off relay and save current state
digitalWrite(relay, LOW);
lampState = "OFF";
Serial.println("Lamp set to OFF\r\n");
textMessage = "";
GPRS.println("AT+CMGS=\"+631234567890\""); /// RECEIVER: change the phone number here with international code
delay(500);
GPRS.print("Lamp was finally switched OFF.\r");
GPRS.write( 0x1a );
delay(1000);
}
if(textMessage.indexOf("STATUS")>=0){
String message = "Lamp is " + lampState;
GPRS.print("AT+CMGF=1");
delay(1000);
Serial.println("Lamp state resquest");
textMessage = "";
GPRS.println("AT+CMGS=\"+631234567890\""); // RECEIVER: change the phone number here with international code
delay(500);
GPRS.print("Lamp is currently ");
GPRS.println(lampState ? "ON" : "OFF"); // This is to show if the light is currently switched on or off
GPRS.write( 0x1a );
delay(1000);
}
}
Change
AT+CNMI=3,3,0,0
to:
AT+CNMI=2,2,0,0,0
The simplest way is the best way.
// if You use SoftwareSerial lib, declare object for GSM
SoftwareSerial gsm(8,9); // TX, RX
void setup(){
// initialise UART and GSM communication between Arduino and modem
Serial.begin(115200);
gsm.begin(115200);
// wait 5-10sec. for modem whitch must connect to the network
delay(5000);
// configure modem - remember! modem didn't remeber Your's configuration!
gsm.print("at+cmgf=1\r"); // use full functionality (calls, sms, gprs) - see app note
gsm.print("at+clip=1\r"); // enable presentation number
gsm.print("at+cscs=\"GSM\"\r"); // configure sms as standard text messages
gsm.print("at+cnmi=1,2,0,0,0\r"); // show received sms and store in sim (probobly, I don't compre this settings with app note but it's working :)
}
void loop(){
String response = gsmAnswer();
if(response.indexOf("+CMT:") > 0 ) { // SMS arrived
// Now You can parse Your Message, if You wont controll only LED, just write
if(response.indexOf("LED ON") > 0) {
digitalWrite(LED_PIN, HIGH); // enable it
}else if(response.indexOf("LED OFF") > 0) {
digitalWrite(LED_PIN, LOW); // turn off
}
delay(1000);
}
}
String gsmAnswer(){
String answer;
while(!gsm.available());
while(gsm.available()){
delay(5);
if(Serial.available() > 0){
char s = (char)gsm.read();
answer += s;
}
}
return answer;
}
One think more, incomming sms has the following format:
+CMT: "+48xxxxxxxxx","","17/07/07,21:57:04+08"
Test of arrived messages
You should first know exactly what the response is before attempting to parse it.
Try something simple like the following code (note: untested!) to get a feeling of what you should look for:
void loop() {
if(cell.available() > 0) {
char ch = cell.read();
Serial.print(ch);
}
}
My guess is you'll see more than just a '0' or a '1' :)
void loop() {
while(cell.available() > 0) {inchar = cell.read(); readString+=c;delay(1);} ///can be a delay up to (10) so you can get a clear reading
Serial.print(readString); /// Declare a string " String readString; "
for (i=0; i<200; i++){ /// Serch for the txt you sent up to (200) times it depends how long your ""readString" is
if(readString.substring(i,i+4)=="RING"){ //// I am looking for the word RING sent from my phone
digitalWrite(13,HIGH);
break;
}
}
}
this will help you find the specific word ir your reading (text message)