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Need help to use 16 channel relays with esp8266 Node mcu and blynk app

Yeah i am aware of it. As the nodemcu doesn’t fit on these bread board i usually buy he ESP12E chip and solder it to a breakout board. And i have my lab bench power supply to feed ESP.

I will definitely checkout !! Thank you for the link.

Вариант 1. Сдвиговый регистр. Вариант 2. Использовать UART ESP и на отдельном микроконтроллере реализовать расширение. Вариант 3. Использовать ESP32

I’m using MCP23017 expander to have more inputs/outputs for my NodeMCU.
It have 16 I/O ports and i2c. Im using 8 ports as inputs for logic current sensors (for light on/off state) and 8 ports as outputs to control relays via ULN2803 transistor array to turn on/off lights.
If needed, the setup can be extended to more MCP23017 and ULN2803 .
ULN2803 used to reduce part amount on board. No diodes needed for relay switching
Controlling inputs/outputs for MCP23017 is very easy

MCP23017 is best use for 16 ch input or output.
For relay for loking for 16 ch relay board gor 5v.
Search on google for board.