Thanks for the reply, maybe this will add a bit more info to my problem.
econjack:
First, the statement:
const char* localData = root["variable"];
is not going to compile because an index for an array must be an integral value, not a string.
It does compile and works fine as I have multiple const char* declarations without problem.
Third, why are you making localData a constant?
Because if I remove the constant to just char* it throws this error:
conversion from 'ArduinoJson::JsonVariant' to 'char*' is ambiguous
This is the original code I based my project off of:
Weather-Display/ESP8266_Weather_Display.ino
@thisoldgeek thisoldgeek on Jan 2 add sketch
#include <ArduinoJson.h>
#include <SoftwareSerial.h>
#define SSID "<SSID>" // insert your SSID
#define PASS "<PASSWORD" // insert your password
#define LOCATIONID "<LOCATION>" // location id
#define DST_IP "23.222.152.140" //api.wunderground.com
#define ESP_RST 4
SoftwareSerial lcdSerial(2, 3); // RX, TX for debugging
const int buffer=300;
int passNum = 1;
// Array of desired weather conditions
// These must be in the order received from wunderground!
//
// Also, watch out for repeating field names in returned json structures,
// and fields with embedded commas (used as delimiters)
char* conds[]={"\"city\":","\"weather\":","\"temp_f\":","\"relative_humidity\":","\"wind_dir\":","\"wind_mph\":","\"pressure_in\":"};
int num_elements = 7; // number of conditions you are retrieving, count of elements in conds
char close_brace ='}';
char comma = ',';
void setup()
{ pinMode(ESP_RST,OUTPUT);
reset();
Serial.begin(9600);
Serial.setTimeout(5000);
lcdSerial.begin(9600); // Print to LCD (or similar display)
}
void loop()
{
reset();
delay(5000); //ESP8266 takes a while to restart
// try to connect to wifi
boolean connected=false;
for(int i=0;i<5;i++){
if(connectWiFi()){
connected = true;
break;
}
}
Serial.println("AT+CIPMUX=0"); // set to single connection mode
String cmd = "AT+CIPSTART=\"TCP\",\"";
cmd += DST_IP;
cmd += "\",80";
Serial.println(cmd);
//lcdSerial.println(cmd);
if(Serial.find("Error")) return;
cmd = "GET /api/<YOURKEY>/conditions/q/";
cmd += LOCATIONID;
cmd +=".json";
cmd += " HTTP/1.1\r\nHost: api.wunderground.com\r\n\r\n";
Serial.print(F("AT+CIPSEND="));
Serial.println(cmd.length());
if(Serial.find(">")){
//lcdSerial.print(">");
}else{
Serial.println(F("AT+CIPCLOSE"));
lcdSerial.println(F("?fConnection timeout"));
delay(1000);
return;
}
Serial.print(cmd);
unsigned int i = 0; //timeout counter
char json[buffer]="{"; // array for Json parsing
int n = 1; // character counter for json
for (int j=0;j<num_elements;j++){
while (!Serial.find(conds[j])){} // find the part we are interested in.
String Str1 = conds[j];
for (int l=0; l<(Str1.length());l++)
{json[n] = Str1[l];
n++;}
while (i<60000) {
if(Serial.available()) {
char c = Serial.read();
if(c==',') break;
json[n]=c;
n++;
i=0;
}
i++;
}
if (j==num_elements-1)
{json[n]=close_brace;}
else
{json[n]=comma;}
n++;
}
parseJSON(json);
// Done with processing for now - close connection
Serial.println(F("AT+CIPCLOSE"));
delay(5000);
// Only check weather every 15 minutes
// So you don't go over quota on wunderground (for free api license)
delay(900000);
}
void parseJSON(char json[300])
{
StaticJsonBuffer<buffer> jsonBuffer;
JsonObject& root = jsonBuffer.parseObject(json);
if (!root.success())
{
lcdSerial.print("?fparseObject() failed");
//return;
}
const char* city = root["city"];
const char* weather = root["weather"];
double temp_f = root["temp_f"];
/////////////////////////////////////////////////////////////////////////////////////////////////////////////
const char* humidity = root["relative_humidity"]; //***THIS IS WHAT I WANT TO PASS*****
////////////////////////////////////////////////////////////////////////////////////////////////////////////
const char* wind_dir = root["wind_dir"];
double wind_mph = root["wind_mph"];
const char* pressure_in = root["pressure_in"];
// location of conditions
lcdSerial.print("?f ");
lcdSerial.print(city);
// Conditions: Sunny, Cloudy, Fog, Rain, etc.
lcdSerial.print(F("?n"));
lcdSerial.print(weather);
// Temp
lcdSerial.print(F("?n"));
lcdSerial.print((int)temp_f);
lcdSerial.print(F("F|"));
// Humidity
lcdSerial.print(humidity);
lcdSerial.print(F("|"));
// Wind Direction
lcdSerial.print(wind_dir);
lcdSerial.print(F(" "));
// Wind Speed
lcdSerial.print((int)wind_mph);
lcdSerial.print(F(" "));
lcdSerial.print(F("MPH"));
// Barometric Pressure
lcdSerial.print(F("?nBarometer: "));
lcdSerial.print(pressure_in);
}
void reset()
{
digitalWrite(ESP_RST,LOW);
delay(100);
digitalWrite(ESP_RST,HIGH);
}
boolean connectWiFi()
{
Serial.println(F("AT+CWMODE=1"));
String cmd="AT+CWJAP=\"";
cmd+=SSID;
cmd+="\",\"";
cmd+=PASS;
cmd+="\"";
Serial.println(cmd);
delay(2000);
if(Serial.find("OK")){
lcdSerial.println(F("?fConnected to WiFi..."));
delay(500); // Allow display to print
return true;
}else{
lcdSerial.println(F("?fCan't Connect..."));
delay(500);
return false;
}
}
In that code I commented the line with the local humidity value I'm trying to pass to a global variable.
(puke):
