Get data from the server on start

Issues and Errors
1

Hi,
Could you please help with the Blynk.sync?
I’d like to restore my parameters from the server on the ESP start.

I try to use Blynk.syncVirtual(V1) and even Blynk.syncAll() but nothing causes BLINK_WRITE to trigger.

For tests I have:
V1 - slider (0…1023) to change my LED light. It works when I slide this widget. But it does not restore LED light on start.
V2 - Numeric input (just for test)
V3 - Button to trigger sync manully

Code:

/* Comment this out to disable prints and save space */
#define BLYNK_PRINT Serial

// #include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>

#include <EasyBlynk8266.h>
  
#define ledPin 13
#define RelayPin 12
#define PIN_BUTTON 0

// This function will be called every time Slider Widget
// in Blynk app writes values to the Virtual Pin 1
BLYNK_WRITE(V1)
{
  int pinValue = param.asInt(); // assigning incoming value from pin V1 to a variable
  Serial.print("V1 Slider value is: ");
  Serial.println(pinValue);
  analogWrite(ledPin,pinValue);
}

BLYNK_WRITE(V2)
{
  int pinValue = param.asInt(); // assigning incoming value from pin V2 to a variable
  BLYNK_LOG2("V2 Slider value is: ", pinValue);
}

BLYNK_WRITE(V3)
{
  Serial.println("SyncV2");
  Blynk.syncVirtual(V2);
  delay(1000);
  Serial.println("SyncAll");
  Blynk.syncAll();
}

void setup()
{
  // Debug console
  Serial.begin(115200);
  Serial.println("");
  Serial.println("Starting..");
  delay(2000);

  Serial.println("set Pins..");
  pinMode(ledPin, OUTPUT);      // установка порта на выход для дублирования V1 на Pin 13 (green led)
  analogWrite(ledPin, 1022);  
  pinMode(PIN_BUTTON, INPUT); // кнопка GPIO0

  Serial.println("Starting EasyBlynk8266..");
  EasyBlynk8266.begin();
  Serial.println("EasyBlynk8266 completed.");
  
//  Serial.println("Set V0..");
//  Blynk.setProperty(V0, "offLabel", "Сохранить");  
//  Blynk.setProperty(V0, "onLabel", "Сохранено");  

//  while (Blynk.connect() == false) {  }
  Blynk.syncAll();
  Serial.println("Delay 5 sec..");
  delay(5000);
  Blynk.syncAll();
  Serial.println("Still no sync?");
}

BLYNK_CONNECTED() {
  //get data stored in virtual pins from server
  Serial.println("Sync..");
  Blynk.syncAll();
}

void loop()
{
  EasyBlynk8266.run();
}

I have many debug Serial.print and expect that inside BLYNK_CONNECT a sync will call BLYNK_WRITE(V1) and I’ll see the debug output "V1 Slider value is: "
But:

[6946] Connecting to blynk-cloud.com:80`
[8077] Ready (ping: 53ms).
Sync..
EasyBlynk8266 completed.
Delay 5 sec..
Still no sync?
-= I press the button V3 =-
SyncV2
SyncAll
-= I change V2 =-
[32725] V2 Slider value is: 6
SyncV2
SyncAll

As you can see when I press the button V3 my sync is called explicitly. But the debug output “V3 Slider value is: 6” appears only when I change V2 in the app.
Looks like sync works neither on start (BLYNK_CONNECT) nor by the button.

Thanks in advance

2

Maybe try using the regular Blynk library rather than this unsupported (by Blynk) wrapper library.

Pete.

3

Thank you Pete!
It works with the standard library indeed.

Could you suggest any other way to use a kind of WiFi manager instead of hard coded credentials for WiFi and Auth Token? (To ask them if the connection was unsuccessful)

4

WifiManager works well.

Also, I’d avoid syncAll if I were you.

Pete.

5
6

Sure. I’ve added it for test purposes only, when syncVirtual(V1) didn’t work.

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