ESP8266 Community Forum

- Sun Jan 03, 2021 6:09 pm #90050 Hello!



I have a question: this is a minimal circuit for ESP.

I would like to drive it by microcontroller. My question is:

1) RST and EN pins are connected by resistors to Vcc. If I want to connect it to STM32 (to STM32's GPIOs) should I still use the same 10k resistors (R2 and R3)?
2) Why GPIO16 must be connected to RST?

[RichardS]

- Sun Jan 03, 2021 7:43 pm #90051 You can leave those 2 resistors if you like, if you can guarantee +3.3V and GND with the other uC then you can remove them...

GPIO16 connects to RST so it can pull reset on itself. I think the watchdog can be configured to pull GPIO16.

RichardS

Surplus parts
https://epartsconnect.com

Live realtime stock market prediction website. https://www.stocksignalslive.com my latest creation. Uses AI and machine learning.

New site featuring ESP8266 and ESP32 projects. tutorials, and news.
http://EverythingESP.com

ESP8266.com Founder and Administrator
The Mind Factory (get more from your 3D printer)

Home of the ESP8266, ESP8285, and ESP32 microcontrollers....

- Mon Jan 04, 2021 8:27 am #90065 the connection between gpio16 and rst is necessary as workaround for a design flaw in deepsleep:
If a) you don't plan to use deepsleep - forget ist
b) plan to use deepsleep - don't use direct connection, use schottky diode with cat to gpio16
(explanation: during deesleep gpio16 is strong vcc so you would not be able to reset esp)

- Wed Jan 06, 2021 12:29 pm #90101 Thank you for the replies:)

1) @RichardS Ok, so what is the real difference between setting binary 1 or binary 0 through 10k resistors or not, on RST and EN by voltage from Vcc or from microcontroller's own GPIOs?

2) The diode will be a great idea, thank you!:)