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nodemcu / nodemcu-firmware

Lua based interactive firmware for ESP8266, ESP8285 and ESP32
https://nodemcu.readthedocs.io
MIT License
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Relay High On Boot #3465

Closed shakirhussain78652 closed 2 years ago

shakirhussain78652 commented 3 years ago

I am trying to use NODEMCU ESP8266 V2 and a 5v, 4 channel relay module to be turned on wirelessly via a mobile app. However every time I power on the circuit. All the relays get activated. I have tried every pin from D1 TO D7. Still facing the same problem. Please help.

chathurangawijetunge commented 3 years ago

can't tell anything without seeing the code.

vsky279 commented 2 years ago

Isn't it due to pin states during boot? https://www.esp8266.com/viewtopic.php?f=32&t=16141

Hey, GPIOs 4 and 5 are the only ones that are always high impedance. All others do have internal pull-ups or are even driven low/high during boot.

GPIOs 3, 12, 13 and 14 pulled HIGH during boot. Their actual state does not influence the boot process.

GPIOs 0, 1, 2 and 15 are pulled HIGH during boot and also driven LOW for short periods. The device will not boot if 0, 1 or 2 is driven LOW during start-up.

GPIO 16 is driven HIGH during boot, don't short to GND.

marcelstoer commented 2 years ago

Nothing the NodeMCU firmware can influence.

TerryE commented 2 years ago

@shakirhussain78652 I drive 4 power SSRs directly from my ESP board. These require 5V @ 50 mA IIRC. The way I do this is to use a MSP23008 with its VCC at 5V direct from my 5V PSU. It interfaces to the ESP via I2C This is at a 3.3V float high reference with both ends doing pull down to GND as necessary. The MSP23008 works fine with 0/3.3V signalling. An no startup pulse issues.