Blynk IOT with Node Red and correct button flow

Blynk 2.0
1

Hi, i have a Siemens LOGO 8 which i communicate with (S7 protocol) via Node Red and Blynk. There is no code, just Node Red handling things.

The LOGO is used to control the automatic cleaning (flushing) of the drumfilter for my Koi pond, one of the (multiple) other things it also controls is e.g. a simple on/off button for the pump.

For now i use the following flow for buttons

flow buttons
flow buttons869Ă—230 11.5 KB

It reads the button status from blynk datastream, when stream is 1 (button on) it sends a True command to a network switch in the LOGO and the pump is switched on.
The second half i use now as live feedback from it’s status in the LOGO back to Blynk.

But… is the second half of the flow necessary or right? and how to do it otherwise?

2

Personally, I wouldn’t feedback to the same virtual pin - it doesn’t really achieve anything as far as I can see.
It would maybe better to feed back the status to an LED widget on a different virtual datastream?

Pete.

1 Like
3

Thanks Pete,

The reason why i have done this was to set the buttons to last (default on) value in the app after a restart of the app…

I will skip all feedback parts in the button flows because i do have status feedback to LED’s in Blynk.
I use the available status from the relais outputs in the LOGO “software” for that.

Like this:

Knipsel
Knipsel1209Ă—355 18.1 KB

DB1,X1064.2 is status of output Q3 (True or False).

4

When you open the Blynk app on a mobile device it will display the value that is currently stored on the server. No need to update this value again.

Pete.

5

Ok, clear. Thanks!