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Digitalwrite in timer does not work

Hello,

i’m trying to have my window blinds/rollers being opened by ESP32/Blynk. I was inspired by It's possible push a virtual button and disable other button? - #12 by Blynk_Coeur

But when adding a digitalWrite (for steering my relays) in the function that was called by the timer, the ESP32 rebooted when coming in this part of the code. When i removed the digitalWrite, all works fine.

Does anybody know why this happens and how it can be solved?

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void loop()

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Are you using blynk legacy or IOT ?
And post the sketch you’re using please.

Do you use a relay board ?
Did you try to use 2 power supplies , one for esp32 and one for the relay board?
I suspect a power loss.

Hi John,
i’m using Blynk legacy.
I indicated the added code by /added code/ . Without the added code if works fine, with the added code, the device reboots/stalls when triggering the rollerup-button.

[Unformatted code removed by moderator]

Hi Blynk_Coeur,
i’m using an simple 2 module relay (https://cdn.myonlinestore.eu/e40d5160-bac0-4897-baae-d6065a5d5915/image/cache/full/97ce289cafaef9a4e1728627e66b5906ef3949a1.jpg)

I doubt power loss, since by triggering the relay in the button push (no timer), it works just fine and stable.

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First, this is not the whole sketch

Second, please edit your post and add triple backticks at the beginning and the end of your sketch, triple backticks look like this```

It’s much easier to create a similar project in blynk IOT using the automation, I highly recommend you to try it.

John, Blynk_Coeur, thanks for your advice. Meanwhile i found the problem: power loss of the ESP32 due to triggering of the relay. Blynk_Coeur you were spot on. I was confused because i hadn’t any issues directly in the button routine, but the timespan for the relay was much shorter (1 ms vs 10ms) there.

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