Option to upload config file via web dashboard

We use spiffs storage on the esp32 to store the config of a device.

I tried to use the text input widget but this allows max 255 characters, any chance this can be enlarged (our JSON config file is 9kB) or a seperate widget is created that enables to send larger text or file?
Or is there a different way?

If this is possible we can do a full ota via Blynk (so firmware and config)

You could probably modify the Blynk.Air functionality to meet your needs.

Maybe add a tab with data in your particular format then copy that data to your SPIFFS file?


We, of course, can allow to send 9k of bytes via text input. However, I’m not sure esp32 will be capable of handling that big request. @vshymanskyy WDYT?

@PeteKnight, thx for thinking along, that could be an option as a work around but difficult to maintain with different devices with different config.

We do not have standard config items, the config file states what kind of sensor is connected to which terminal ie:

"sensors": [
      "name": "TempOutside",
      "type": "ADCThermistor",
      "id": 13,
      "terminalId": 9,
      "pollingInterval": 30000,
      "vRefNodeId": 23
      "name": "LightZone5",
      "type": "PWM",
      "id": 34,
      "terminalId": 51,
      "pinMode": "OUTPUT",
      "storage": "pwm",
      "key": "lz5"
      "name": "Boiler State",
      "type": "MxDigital",
      "id": 111,
      "terminalId": 10,
      "interruptEnabled": true,
      "pollingInterval": 10000

@Dmitriy, not sure how it goes via a write virtual pin upload but esp can handle a 2MB firmware download write to spiffs if you ota so I guess the 9k should not be an issue. If you make it possible in a beta widget (sizable/scrollable large text input/output) I would be happy to test it :slight_smile:

Just thought of another option, I could provide a url via a text input and then download it…
But still would be nice if I could show/edit contents in a large text field.

The perfect solution would be if we have the above option and that an additional file (or url) can be provided in an OTA shipment next to the bin file…

I still don’t think it should be done via widget. As this is config. It is not datastream data. So maybe it would be more efficient to use meta fields (but they too have 255 chars limitation) or maybe even a separate config command.

agree it is not datastream and would be a bit misusing a widget for it.

How would I get the value of a meta field to a device?


thank you! Missed that looking though the docs.

This could indeed be an option to store the config url which the esp could check for new/updated config

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