Water Valve Project: Adding Blynk control to previously written code

[Blink_tynker]

oops my mistake … it’s as written (Schematic was wrong) Pin 3 to GND and pin 4 to the GPIOs …
updated the schematic

[PeteKnight]

I thought pin #4 was supposed to be GND?

Pete.

[Blink_tynker]

This where I’m a getting little confused when reading, I’ve seen it written both ways but this way seemed to fit what I was attempting to do.

1. Anode - ‘+’ 24vDC
2. Diode - ‘-’ 24vDC
3. Emitter - ESP32 GND
4. Collector - GPIO 17 or 18

Although I’m making the assumption that this will essentially work as a switch for me, when the diode has ‘-’ power applied (via the valves internal open/close switch) and the pc817 LED is on, a connection is made between the Emitter and collector …essentially connecting the ESP32’s ground to the appropriate GPIO pin, where my code will read it and illuminate the appropriate vLED… Or maybe I have that completely wrong

[PeteKnight]

I was goiung by this:

PC817 Optocoupler Pinout, Working, Applications, Example with Arduino

But I’ve now realised that the diagram labels pin 4 as the Collector, but the description below labels it as the Emitter!!

I’d suggest that you dig-out the manufacturers datasheet and follow that.

Pete.

[Blink_tynker]

ahh I see … that’s why we get confused LOL

Here is the data sheet

PC817%20Datasheet.pdf

It has pin 3 as emitter and pin 4as collector …
So then I guess its pin 3 (emitter) to GND and pin 4 (collector) to the GPIOs

Since I’m still using INPUT_PULLUP, I’m assuming I don’t need a resistor between pins 3 or 4 and the ESP32 as it should work the same way I currently have it set up – GND to valve switch to GPIO … except with this, its GND to PC817 to GPIO, with the PC817 now acting as the valve switch to illuminate the vLEDs after the real valve switch sends current through the PC817

[PeteKnight]

That sounds like a reasonable assumption. I assume that you’ve calculated your 4.7K resistor based on your 24V supply voltage and the datasheet?

Pete.

[Blink_tynker]

correct

@PeteKnight

I assume that you’ve calculated your 4.7K resistor based on your 24V supply voltage and the datasheet?

[Blink_tynker]

// Fill-in information from your Blynk Template here
#define BLYNK_TEMPLATE_ID "TMPLBxxxxxxx"
#define BLYNK_DEVICE_NAME "Water Switches"

#define BLYNK_FIRMWARE_VERSION        "0.1.0"

#define BLYNK_PRINT Serial
//#define BLYNK_DEBUG

#define APP_DEBUG

// Uncomment your board, or configure a custom board in Settings.h
//#define USE_WROVER_BOARD

#include "BlynkEdgent.h"
#define valveRelay 16
#define whRelay 26
#define openPositionGPIO 17
#define closedPositionGPIO 18
#define openLED 21
#define closedLED 22
#define whLED 23
#define vRelayBtn V1
#define v_openLED V2
#define v_closedLED V3
#define vWHBtn V4

void control_LEDs()
{
  if (digitalRead(openPositionGPIO) == HIGH)
  {
    Blynk.virtualWrite(v_openLED,255);
    digitalWrite (openLED,HIGH);
  }
  else
  {
    Blynk.virtualWrite(v_openLED,0);
    digitalWrite (openLED,LOW);    
  }


  if (digitalRead(closedPositionGPIO) == HIGH)
  {
    Blynk.virtualWrite(v_closedLED,255);
    digitalWrite (closedLED,HIGH);
  }
  else
  {
    Blynk.virtualWrite(v_closedLED,0);
    digitalWrite (closedLED,LOW);
  }
}

void setup()
{
  // Debug console
  Serial.begin(115200);
  
  pinMode(valveRelay,OUTPUT);
  pinMode(openPositionGPIO,INPUT_PULLUP);
  pinMode(closedPositionGPIO,INPUT_PULLUP);
  pinMode(openLED,OUTPUT);
  pinMode(closedLED,OUTPUT);
  pinMode(whRelay,OUTPUT);
  pinMode(whLED,OUTPUT);

  BlynkEdgent.begin();
}

BLYNK_WRITE(vWHBtn)
{
  if (param.asInt())
  {       
    digitalWrite(whRelay, HIGH);
    digitalWrite(whLED,HIGH);
  }
  else
  {
    digitalWrite(whRelay, LOW);
    digitalWrite(whLED,LOW);
  }
}
BLYNK_WRITE(vRelayBtn)
{
  if (param.asInt())
  {       
    digitalWrite(valveRelay, HIGH);
  }
  else
  {
    digitalWrite(valveRelay, LOW);
  }
}
void loop() 
{
  BlynkEdgent.run();
}

Hi guys, I’m migrating this to Blynk 2.0 … my buttons in the app seem to work OK to turn each relay on and off, but, I can’t get it to display the virtual led (on/off) in the app …I feel like I’m missing something in the web dashboard of blynk console …
for instance, on the open LED I have Pin=V2, Data Type =Integer, Units=None, Min=0, Max =255(also tried min0/max1) and default value = null

[PeteKnight]

255 should work.
Have you tried adding a display widget attached to the same datastream to see what values you are sending to that datastream?

The Max value of the datastream actually defines what value will give the maximum brightness level of the LED widget. So, if you have a datastream attached to an LED where that datastream’s Max value is 255 and you write 255 to that virtual pin then the LED will be on at full brightness.
If you then change the datastreams Max value to 1023 and deploy the changes, a value of 255 will result in 25% brightness. You would then need to write 1023 to the virtual pin to give maximum brightness.

Pete.

[Blink_tynker]

Thanks Pete, tried the display widget (within the app only)… nothing displays. Thankfully this is not the in use project but a second test set up, so no issues testing . I went back and installed the blynk 1.0 version of the code and virtual LEDs work properly, so its does not appear to be a hardware or wiring issue. The only difference from the original programming is the removal of the

@PeteKnight

timer.setInterval(100,control_LEDs);

as well as timer.run in the void loop

these caused errors during verification, so I removed them… plus I thought I read these were no longer needed in 2.0

Any ideas ?

[Blink_tynker]

Here’s the datastream info for open LED if it helps …

[PeteKnight]

@Blink_tynker

The only difference from the original programming is the removal of the

@PeteKnight

timer.setInterval(100,control_LEDs);

as well as timer.run in the void loop

So how do you think that the control_LEDs() function - which is the only part of the code that writes to the LED widget - is going to be triggered?

@Blink_tynker

I thought I read these were no longer needed in 2.0

Of course it’s still necessary to trigger a function that contains code which needs to be executed, and a timer is the required way to do that in this case.

@Blink_tynker

these caused errors during verification

@Blink_tynker

Any ideas ?

Not without details of what those errors were.

Pete.

[Blink_tynker]

ahh … so its me

ok here is the error

Arduino: 1.8.19 (Windows 10), Board: "ESP32 Dev Module, Disabled, Default 4MB with spiffs (1.2MB APP/1.5MB SPIFFS), 240MHz (WiFi/BT), QIO, 80MHz, 4MB (32Mb), 921600, None"

C:\Users\Donna\Documents\Arduino\Valve_Project__01.18.22__No_Timer-Edgent_ESP32\Valve_Project__01.18.22__No_Timer-Edgent_ESP32.ino: In function 'void setup()':

Valve_Project__01.18.22__No_Timer-Edgent_ESP32:68:3: error: 'timer' was not declared in this scope

   timer.setInterval(100,control_LEDs);

   ^

C:\Users\Donna\Documents\Arduino\Valve_Project__01.18.22__No_Timer-Edgent_ESP32\Valve_Project__01.18.22__No_Timer-Edgent_ESP32.ino: In function 'void loop()':

Valve_Project__01.18.22__No_Timer-Edgent_ESP32:98:5: error: 'timer' was not declared in this scope

     timer.run();

     ^

Multiple libraries were found for "BlynkSimpleEsp32_SSL.h"

 Used: C:\Users\Donna\Documents\Arduino\libraries\blynk-library-master

 Not used: C:\Users\Donna\Documents\Arduino\libraries\Blynk

Multiple libraries were found for "WiFi.h"

 Used: C:\Users\Donna\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.5\libraries\WiFi

 Not used: C:\Program Files (x86)\Arduino\libraries\WiFi

exit status 1

'timer' was not declared in this scope



This report would have more information with
"Show verbose output during compilation"
option enabled in File -> Preferences.

and the code

// Fill-in information from your Blynk Template here
#define BLYNK_TEMPLATE_ID "TMPLBQenu4Rw"
#define BLYNK_DEVICE_NAME "Water Switches"

#define BLYNK_FIRMWARE_VERSION        "0.1.0"

#define BLYNK_PRINT Serial
//#define BLYNK_DEBUG

#define APP_DEBUG

// Uncomment your board, or configure a custom board in Settings.h
//#define USE_WROVER_BOARD

#include "BlynkEdgent.h"
#define valveRelay 16
#define whRelay 26
#define openPositionGPIO 17
#define closedPositionGPIO 18
#define openLED 21
#define closedLED 22
#define whLED 23
#define vRelayBtn V1
#define v_openLED V2
#define v_closedLED V3
#define vWHBtn V4

void control_LEDs()
{
  if (digitalRead(openPositionGPIO) == HIGH)
  {
    Blynk.virtualWrite(v_openLED,255);
    digitalWrite (openLED,HIGH);
  }
  else
  {
    Blynk.virtualWrite(v_openLED,0);
    digitalWrite (openLED,LOW);    
  }


  if (digitalRead(closedPositionGPIO) == HIGH)
  {
    Blynk.virtualWrite(v_closedLED,255);
    digitalWrite (closedLED,HIGH);
  }
  else
  {
    Blynk.virtualWrite(v_closedLED,0);
    digitalWrite (closedLED,LOW);
  }
}

void setup()
{
  // Debug console
  Serial.begin(115200);
  
  pinMode(valveRelay,OUTPUT);
  pinMode(openPositionGPIO,INPUT_PULLUP);
  pinMode(closedPositionGPIO,INPUT_PULLUP);
  pinMode(openLED,OUTPUT);
  pinMode(closedLED,OUTPUT);
  pinMode(whRelay,OUTPUT);
  pinMode(whLED,OUTPUT);

  timer.setInterval(100,control_LEDs);
  BlynkEdgent.begin();
}

BLYNK_WRITE(vWHBtn)
{
  if (param.asInt())
  {       
    digitalWrite(whRelay, HIGH);
    digitalWrite(whLED,HIGH);
  }
  else
  {
    digitalWrite(whRelay, LOW);
    digitalWrite(whLED,LOW);
  }
}
BLYNK_WRITE(vRelayBtn)
{
  if (param.asInt())
  {       
    digitalWrite(valveRelay, HIGH);
  }
  else
  {
    digitalWrite(valveRelay, LOW);
  }
}
void loop() 
{
    timer.run();
    BlynkEdgent.run();
}

[PeteKnight]

@Blink_tynker

error: 'timer' was not declared in this scope

You’re missing this line of code…

@PeteKnight

BlynkTimer timer;

Pete.

[Blink_tynker]

@PeteKnight

BlynkTimer timer;

It works !! Pete … you da man!!!

Now that it works, I wanted to try and get this to work via Alexa commands. I read this comment by you

@PeteKnight

I’ve recently migrated to the node-red-contrib-virtual-smart-home plug-in which is much easier to use and (so far) is much more reliable than the node-red-contrib-alexa-home-skill that I was using before.
This plug-in also allows a much wider range of device types to be used

Which led me to these instructions … does that put me on the right path or do you have a better approach

node-red-contrib-virtual-smart-home

I’ve never used node red
Thanks again, Jack

[John93]

Check this out

My home automation projects built with MQTT and Node Red

Update January 2022 Okay, it’s been almost 3 years since my last post in this topic, and things have changed quite a bit – so it’s time for an update…. New Blynk IoT Obviously, the main thing that’s changed since my last update is the launch of the new Blynk IoT system (AKA Blynk 2.0). This required some changes to the Node-Red contrib for Blynk, so a new contrib called node-red-contrib-blynk-iot has been launched. The current version of this contrib is 0.2.0 and the following warning… [image…

[PeteKnight]

Moving to Node-Red is quite a big step, as the best approach is to use MQTT to communicate between Node-Red and your devices, and run no Blynk code on your devices at all.

You could go for an intermediate solution, which simply uses Node-Red as the tool to provide Alexa integration by using commands from Alexa to change the state of Blynk virtual pins.
You could do this on a Windows machine as a trial, but longer term you’d be better running a Raspberry Pi to host Node-Red.

Adding Sinric or FauxmoESP to your sketch is an alternative approach, but isn’t something I’ve ever tried.

Pete.

[Blink_tynker]

OK, I ended up trying Voiceflow instead and have it working in the online creator for Alexa, under my blink 1.0 project. Now I’m trying to make this work with Blynk Iot … but I get an “Invalid token.” message whether I ping directly or via the voiceflow interface . The token I’m using is from the ‘device info’ tab of blynk console under FIRMWARE CONFIGURATION … I assume this is the correct token … so maybe voiceflow wont work with blynk 2.0
Any suggestions ?

http://blynk-cloud.com/my token/update/V1?value=1
http://blynk-cloud.com/my token/get/v1

[PeteKnight]

You are trying to make an API call to the Legacy server, using a Blynk IoT token, which is why you are getting the Invalid Auth Token message.

You need to use the Blynk IoT token with the Blynk IoT API syntax, and specify the correct Blynk IoT server.

Here is the documentation for the correct syntax:
https://docs.blynk.io/en/blynk.cloud/https-api-overview

and in particular you should read the “Troubleshooting” section to get the correct server name…

Pete.

[Blink_tynker]

As usual … Thanks Pete !! Looks like I had the whole string wrong !

For anyone else looking for the correct strings for GET and Update value API if your using Voiceflow dot com (you get 2 free projects) to provide voice commands to your project via Amazon’s Alexa.

You may see these in your research, but, these are all the wrong strings for Blynk IoT (aka Blynk 2.0)

GETs
http://188.166.206.43/{your token}/get/{requested pin} (only works for legacy Blynk)
http://blynk-cloud.com/{your token}/get/{requested pin} (only works for legacy Blynk)
https://blynk.cloud/external/api/get?token=**{token}**&**{pin}**
Update Value
http://188.166.206.43/**{token}**/update/**{Pin}**?value=**{value}** (only works for legacy Blynk)
http://blynk-cloud.com/{token}/update/**{Pin}**?value=**{value}** (only works for legacy Blynk)
https://blynk.cloud/external/api/update?token=**{token}**&**{pin}**=**{value}**

Correct ‘GET’ string

https://{region}.blynk.cloud/external/api/get?token={token}&{pin}

Where the region(in my case ny3) depends on the region that displays in the bottom right corner of your browser, when you’re on the ‘Blynk console’ web page for your projects.

Get Value Documentation

https://docs.blynk.io/en/blynk.cloud/get-datastream-value

Same goes for region in the string for updating a pin

https://{region}.blynk.cloud/external/api/update?token={token}&{pin}={value}

Update data stream value Documentation

https://docs.blynk.io/en/blynk.cloud/update-datastream-value