ESP8266 NodeMcu turns on All my relays when powered on?

[Tayyabhamza]

Please help me what should i do,
When I power on the nodemcu board It turns on my all relays.
Whats the problem is?

[PeteKnight]

You should add pinMode and digitalWrite statement to your void setup to resolve this.
You should also ensure that you are using appropriate pins for your relays…

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…

Pete.

[Blynk_Coeur]

There are only 2 low pins on NodeMcu at start
GPIO4 and GPIO5

Pins HIGH at Boot

GPIO16
GPIO3
GPIO1
GPIO10
GPIO9

Pins used during Boot

• GPIO16: pin is high at BOOT
• GPIO0: boot failure if pulled LOW
• GPIO2 : pin is high on BOOT, boot failure if pulled LOW
• GPIO15 : boot failure if pulled HIGH
• GPIO3 : pin is high at BOOT
• GPIO1 : pin is high at BOOT, boot failure if pulled LOW
• GPIO10 : pin is high at BOOT
• GPIO9 : pin is high at BOOT