Nodejs: How do I read the value of a VPin w/o changing its value

Solved
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My environments are:
Windows 10
Windows VS Code
Python 3. Client
node 9.3
nodejs Library 4.7

Raspberry Pi
Pythion 3
node 9.3
nodejs Library 4.7

I want to know the brightness level of an LED on my android phone which is set on the phone using a slider so that I can return it to that setting after blinking it at full brightness to bring attention to a situation.

Just getting started but everything else seems to work using LEDs on and off, LCDs, Value, Slider & Gauges w/o any code changes moving from Windows 10 to Raspberry Pi… a great development environment.

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Your question is more along the “How to program in NodeJS?” then a Blynk specific issue. We try to assist with the learning about Blynk and it’s commands… not so much on the 'teach how to code" :stuck_out_tongue_winking_eye: There are already many sites and resources for that.

Unfortunately, there is currently very little in the range of Blynk NodeJS examples… but searching this forum for key words will reveal them… as well as reading this site

Meanwhile, reading a Virtual pin state or value is always done without affecting same data… it is just up to you to interpret and utilise it.

var pinValue  // Setup variable
var MyPinV0 = new blynk.VirtualPin(0);  // Setup Virtual Pin with identifying name

// Function that reads the value of a slider
MyPinV0.on('write', function(param) {  // Watches for V0 Slider
pinValue = param;  // "load" the slider value into the variable pinValue
// The rest of your code that does something with the data
});
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Hello,
I know that the topic is very old, but my problem is linked with it and it’s very new.
Gunner, because you wrote the comment that is very close to what I need, Im asking you, what if on Virtual Pin 0 was not a slider, but a Display Data Widget. What will the code be? I hope you understood my idea an Im waiting for your answer.
Thank you.

4

Hello. I think your issue is related only in being about Python, not what the OP was asking. But here…

Since the Display widget is an input, you would use an output type command, for example if display is on V0 you use (note you use lower case and do NOT use the V in Python)…

blynk.virtual_write(0,"Hello Blynkers")

You can probably get a good understanding of Blynk Python commands from the examples available in the library…

Please create a new topic with details about your project if you have further questions. Thanks.

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