ESP8266 Unreachable

I'm a beginner who is trying to link the esp8266 to an arduino uno card. I've been following a lot of tutorials and even with these i can't get a result. I added this link in the preferences https://arduino.esp8266.com/stable/package_esp8266com_index.json and i did this plan

. In the IDE, I have also downloaded the ESP8266 in the board manager. When i choose the arduino uno baord and COM3 port i can't see any response when sending AT in serial monitor. I have a problem in linking the both components. I'll be so grateful if someone could help me.

connect rx to tx and vise versa. it seems to me you connected rx to rx and tx to tx?

To be honest i've done all possibilites of linking. I guess my problem is when i'm going an IDE.

I moved your topic to an appropriate forum category @waylow.

In the future, please take some time to pick the forum category that best suits the subject of your topic. There is an "About the _____ category" topic at the top of each category that explains its purpose.

This is an important part of responsible forum usage, as explained in the "How to get the best out of this forum" guide. The guide contains a lot of other useful information. Please read it.

Thanks in advance for your cooperation.

A Uno operates on 5V, an ESP8266 on 3V3. You must use a voltage divider from the Uno Tx to the ESP Rx. From my own mistakes I can tell you that even if the voltage on the Rx pin is just a little bit higher than the supply voltage then the ESP will do weird things.

In addition to that a Uno has only 1 serial port, which is used by the serial monitor and to upload code. If you have anything else connected to the serial port while trying to upload code it will probably fall. Try uploading the code with nothing else connected to the Uno.

In my opinion trying to get a Uno to communicate with an ESP is not a beginner project.

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This is actually the correct connections in the odd use case where the UNO is being used as a USB to serial adapter instead of an actual Arduino board.

The reason is that the purpose of this circuit is to connect the USB to serial bridge chip on the UNO (e.g., ATmega16U2) to the ESP8266. The labels on the pins on the UNO are in relation to the pins on its primary ATmega328P microcontroller chip, not the USB to serial bridge chip. The bridge chip has an RX-TX, TX-RX connection to the ATmega328P, so the pin labeled "RX" on the UNO is actually connected to the TX pin on the bridge chip, and the pin labeled "TX" on the UNO is connected to the RX pin on the bridge chip. So these connections are actually an RX-TX, TX-RX connection between the bridge chip and the ESP32.


@waylow in addition to the good advice from @PerryBebbington, I would also recommend you to connect the RESET pin on the UNO to the GND pin. The reason is that if the sketch that happens to be running on the UNO's ATmega328P does any serial communication then that can interfere with the communication between the UNO's USB to serial bridge chip and the ESP32. Holding the ATmega328P in reset prevents its program from running and thus any chance of interference.

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You guys are saying interesting stuffs but are you sure the problem is that hard, in my opinion can't it be just a step that i skipped or anything i'm doing bad ?
Btw when i've watched tutorials guys had the same assembly as mine.

But on this one i have not plugged the 3v3 to reset esp8266's pin.

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