Arduino json and wifiesp crash

Projects Programming
1

This is the code to get weather information from openweathermap

#include "WiFiEsp.h"
#ifndef HAVE_HWSERIAL1
#include "SoftwareSerial.h"
//#include <ArduinoJson.h>
//#include <Arduino_JSON.h>
SoftwareSerial ETH_ESP_01(6, 7); // RX, TX
#endif

const char ssid[] = "SK_WiFiGIGA6E56";            // your network SSID (name)
const char pass[] = "********";        // your network password
int status = WL_IDLE_STATUS;     // the Wifi radio's status

char server[] = "api.openweathermap.org";
String result = "";

// Initialize the Ethernet client object
WiFiEspClient Ethclient_ESP_01;

void setup()
{
  // initialize serial for debugging
  Serial.begin(9600);
  // initialize serial for ESP module
  ETH_ESP_01.begin(9600);
//  pinMode(10, OUTPUT);
//  digitalWrite(10, LOW);
//  delay(100);
//  digitalWrite(10, HIGH);
//  delay(500);

  WiFi.init(&ETH_ESP_01);

  // 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 WPA SSID: ");
    Serial.println(ssid);
    // Connect to WPA/WPA2 network
    status = WiFi.begin(ssid, pass);
  }

  // you're connected now, so print out the data
  Serial.println("You're connected to the network");
  
  printWifiStatus();

  Serial.println();
  Serial.println("Starting connection to server...");
  // if you get a connection, report back via serial
  if (Ethclient_ESP_01.connect(server, 80)) {
    Serial.println("Connected to server");
    // Make a HTTP request
    Ethclient_ESP_01.println("GET /data/2.5/weather?id=1838519&appid=token HTTP/1.1");
    Ethclient_ESP_01.println("Host: api.openweathermap.org");
    Ethclient_ESP_01.println("Connection: close");
    Ethclient_ESP_01.println();
  }
}

void loop() {
  result.reserve(1024);
  bool i = false;
  while (Ethclient_ESP_01.available()) {
    char c = Ethclient_ESP_01.read();
    result += c;
  }
  Serial.println(result);

  int first = result.indexOf("{");
//  result = result.substring(first+1);
  result.remove(0, 318);
  
  ETH_ESP_01.println(result);
  ETH_ESP_01.println(first);

  

  
  JSONVar myArray = JSON.parse(result);

  if (JSON.typeof(myArray) == "undefined") {
    Serial.println("Parsing input failed!");
  }

  Serial.println(myArray["name"]);


//  StaticJsonDocument<512> doc;
//  DeserializationError error = deserializeJson(doc, result);
//
//  if (error) {
//    Serial.print(F("deserializeJson() failed: "));
//    Serial.println(error.f_str());
//  }

  // if the server's disconnected, stop the client
  if (!Ethclient_ESP_01.connected()) {
    Serial.println();
    Serial.println("Disconnecting from server...");
    Ethclient_ESP_01.stop();

    // do nothing forevermore
    while (true);
  }
}


void printWifiStatus()
{
  // print the SSID of the network you're attached to
  Serial.print("SSID: ");
  Serial.println(WiFi.SSID());

  // print your WiFi shield's IP address
  IPAddress ip = WiFi.localIP();
  Serial.print("IP Address: ");
  Serial.println(ip);

  // print the received signal strength
  long rssi = WiFi.RSSI();
  Serial.print("Signal strength (RSSI):");
  Serial.print(rssi);
  Serial.println(" dBm");
}

Works well in this state, normal result:

{"coord":{"lon":129.05,"lat":35.1333},"weather":[{"id":800,"main":"Clear","description":"clear sky","icon":"01n"}],"base":"stations","main":{"temp":285.15,"feels_like":283.71,"temp_min":285.15,"temp_max":285.15,"pressure":1018,"humidity":50},"visibility":10000,"wind":{"speed":2.06,"deg":200},"clouds":{"all":0},"dt":1618486591,"sys":{"type":1,"id":8086,"country":"KR","sunrise":1618433511,"sunset":1618480530},"timezone":32400,"id":1838519,"name":"Busan","cod":200}

However, if you run Arduino Json.h or Arduino_JSON.h on this code, the result will be strange.
Abnormal result value :

{"coord":{"lon":129.05,"lat":35.1333},"weather":[{"id":800,"main":"Clear","description":"clear sky","icon":"01n"}],"base":"stations","main":{"temp":285.15,"feels_like":283.71,"temp_min":285.15,"temp_max":285.15,"pressure":1018,"humidity":50},"visibility":10000,"wind":{"speed":2.06,"deg":200},"clouds":{"all":0},"dt":1618486591,"sys":{"type":1,"id":8086,"country":"KR","sunrise":1618433511,"sunset":161848053

I use Arduino Uno and ESP-01 module
How can I solve this problem?

2

where do you have this definition from?

    JSONVar myArray = JSON.parse(result);

I tried to find the letter-sequence "JSONVar" inside the JSON-library-file not a single hit

all I could find was "JsonVariant"

I don't think that this is a valid statement

Serial.println(myArray["name"]);

if myArray is a real array the value between the rectangular brackets has to be a positive integer-value.

JSON itselfs deals a lot of with strings but at this place I guess it must be an integer

best regards Stefan

3

you have StaticJsonDocument<512> doc
--> is 512 enough ?
--> do you have memory left in your UNO to come with run time needs?

if you don't care about the full answer, may be you can use a parser (in ArduinoJson) to only keep the relevant piece of the stream

4

This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.