How send data from UNO R4 to windows (python)

Official Hardware UNO Family UNO R4 WiFi
1

Hello all, many day can not figure out, how I can send data from UNO R4 to python script. I just need for test send one value. I created the next script and can send data, but I can not send this data in loop. Can you give me some advice how I can do it ?

#include "WiFiS3.h"
char ssid[] = "123451";
char pass[] = "12341";
int status = WL_IDLE_STATUS;
WiFiServer server(80);

void setup() {
  Serial.begin(9600);
  while (status != WL_CONNECTED) {
    status = WiFi.begin(ssid, pass);
    delay(10000);
  }
  server.begin();
}
 
void loop() {
  int tests = 1;
  WiFiClient client = server.available();
  if (client) {    
    String currentLine = "";
    while (client.connected()) {  
      char c = client.read();
      if (c == '\n') {    
        if (currentLine.length() == 0) {
          client.println("HTTP/1.1 200 OK");
          client.println("Content-type:text/html");
          client.println();
          
          while (1) {
            tests += 1;
            client.print(tests);
            client.println();
          }
          client.println();
        } else {
          currentLine = "";
        }
      } else if (c != '\r') {
        currentLine += c;
      }
    }
  }
}
3

I've written a small tutorial on interfacing with Python. See Two ways communication between Python3 and Arduino

4

You could write a Flask application and send the data over with a HTTP-POST request.

5

If I understand your code, you wish to receive data over the network. Before doing a

client.read();

You should check to see if any data is waiting to be read. To do this, you might do something like this:

while (client.connected()) {
      if (not client.available()) {
        continue;
      }
      char c = client.read();

Perhaps you could provide a better description of how your code is supposed to work. It may be easier to forget about HTTP initially, use a Python socket to interact with the Arduino, and then convert to HTTP when everything works.

6

Thank you! Sorry for late response, I didn't receive notification.
Actually, I need oppositely, send data from Arduino to Python. It works via HTML (web server) but very slowly.

#include "WiFiS3.h"

char ssid[] = "";
char pass[] = "";
int status = WL_IDLE_STATUS;
WiFiServer server(80);

void setup() {
  Serial.begin(9600);
  while (status != WL_CONNECTED) 
    {
    status = WiFi.begin(ssid, pass);
    }
  server.begin();
}
  int a = 0;
void loop() {

  WiFiClient client = server.available();
    client.println("HTTP/1.1 200 OK");
    client.println("Content-type:text/html");
  //  int c = 8;
  //  client.print(c);

    String currentLine = "";
    while (client.connected()) {
      if (client.available()) {
        char c = client.read();
        if (c == '\n') {
          if (currentLine.length() == 0) {
            client.println();
            a += 1;
            client.print(a);
            break;
          } else {
            currentLine = "";
          }
        } else if (c != '\r') {
          currentLine += c;
        }
      }
    }
    client.stop();
    Serial.println("Client disconnected.");
}
7

Thank you! looks like your tutorial for Serial, I need wifi

8

Below is both a sketch and Python script to implement a simple UDP server residing on your PC and a client residing on the Arduino R4 WIFI.

Client Sketch

/*
  WiFi UDP Send data

  

*/
#include <WiFiS3.h>

int status = WL_IDLE_STATUS;
char ssid[] = "";      // your network SSID (name)
char pass[] = "";  // your network password (use for WPA, or use as key for WEP)
char remote_pc_ip[] = "192.168.1.231";
int keyIndex = 0;           // your network key index number (needed only for WEP)



char SendBuffer[] = "1";  // a string to send back

WiFiUDP Udp;


void setup() {
  //Initialize serial and wait for port to open:
  Serial.begin(115200);
  while (!Serial) {
    ;  // wait for serial port to connect. Needed for native USB port only
  }

  // check for the WiFi module:
  if (WiFi.status() == WL_NO_MODULE) {
    Serial.println("Communication with WiFi module failed!");
    // don't continue
    while (true)
      ;
  }

  String fv = WiFi.firmwareVersion();
  if (fv < WIFI_FIRMWARE_LATEST_VERSION) {
    Serial.println("Please upgrade the firmware");
  }

  // attempt to connect to WiFi network:
  while (status != WL_CONNECTED) {
    Serial.print("Attempting to connect to SSID: ");
    Serial.println(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:
    delay(10000);
  }
  Serial.println("Connected to WiFi");

  Serial.println("\nStarting connection to server...");
  // if you get a connection, report back via serial:
  Udp.begin(50008);
}

void loop() {

  // if there's data available, read a packet

  // send a reply, to the IP address and port that sent us the packet we received
  Udp.beginPacket(remote_pc_ip, 50007);
  Udp.write(SendBuffer);
  Udp.endPacket();
  SendBuffer[0]++;
  delay(1000);
}

Before compiling and uploading, you must enter your SSID, password, and PC IP address at the top of the sketch.

Python Server

import socket

ServerSocket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
host = '0.0.0.0'
port = 50007

try:
    ServerSocket.bind((host, port))
except socket.error as e:
    print(str(e))


while True:
    data, address = ServerSocket.recvfrom(2048)
    data_str = data.decode('utf-8')
    try:

        # print(f"data : {data_str}, address : {address}")
        print(f'data received: {data_str}')

    except:
        print(f"invalid value, data : {data_str}, address : {address}")

    if not data:
        print("no data")
        break

connection.close()

No modifications are necessary for the server.

Start the server and then power up the Uno R4. The value should increase by one every second.

9

thank you!

10

const char for ssid, pass, remote_pc_ip

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