Problem with virtual pins and if command (ESP 8266)

[PeteKnight]

@Mauro_merkel

9 relays

You can’t use 9 relays successfully with a NodeMCU, there aren’t enough suitable pins. You should read this:

ESP8266 GPIO pins info, restrictions and features

hi blynkers! the esp8266 mcu is widely used in iot projects. however, most gpio pins on this mcu have special / multiple functionality and are not safe to use in all circumstances. these “features” are still not well documented and not explained in a friendly manner for newbies. i see lots of cases when the “issues” are simply caused by not knowing which pins to use in which case. [esp8266 pin features] here is a basic table for startup. i’ve collected the info from various sources on the i…

You should use an ESP32 instead, or a port expander on the NodeMCU.

Your void loop isn’t suitable for use with Blynk. You should read this…

http://help.blynk.cc/getting-started-library-auth-token-code-examples/blynk-basics/keep-your-void-loop-clean

@Mauro_merkel

When I turn on the nodemcu the 9 relays turn ON, I can’t find a way that when the system starts they all start off in OFF.

Add virtualWrite commands to your void setup to set the status that you want.

@Mauro_merkel

I need when I press a button1 in my blynk app through the virtual pin V1, turn on R1, R8 and R3 … when the virtual pin V1 goes to 0, R1, R8 and R3 should be turned OFF.

Read this…

Using Virtual Pins to control physical devices

I thought I’d write a guide about how to use virtual pins with app widgets such as buttons, to control physical devices such as relays, LEDs etc… Why use virtual pins anyway? I’d always recommend using virtual pins over physical pins when developing your code. There are a number of reasons, but here are what I consider to be the main ones: Virtual pins are hardware independent. This means that it’s far easier to port your code from one hardware platform to another in future (when you realise…

Pete.