We are trying to make esp8266 to send data from ina219 to website. Firstly we are trying to connect Arduino UNO with ESP8266-01, we have uploaded simple check sketch it was successfully uploaded, but it doesn’t answered to AT commands. Please help with this issue.
You have to connect Rx → Tx and Tx → Rx when working with serial communications.
In addition, both devices need to be talking to each other at the same baud rate. Have you checked what baud rate the ESP-01 is currently using?
Has the ESP-01 ever been flashed with sketch, or is it brand new out of the packet from the factory?
Also, the GPIO 0 and 1 pins on the Uno are connected to the USB connector on the board. This means that if you connect your ESP–01 to the Uno in this way, you lose all serial debugging capabilities. That’s why most Uno users use SoftwareSerial to create a second serial port to connect the ESP-01 to. This has the disadvantage that the maximum baud rate is 9600, so the ESP-01 has to be told to work at this speed if it isn’t already.
When we connect RX - TX, TX - RX, then everything stops working for us and the following error comes out: espcomm_upload_mem failed. So we connected like this.
I didn’t quite understand what you meant about GPIO 0.
We bought esp8266-01 new, and tried to run different codes on Arduino IDE, because every time an error came out.
This is because you have your ESP-01 connected to the Rx and Tx pins on the Uno (GPIO 0 & 1, or D0 and D1 if you prefer).
These pins are also connected to the large USB connector on your Uno, which is what you are using to upload your sketch, and where you would normally obtain your serial debug data from. You can’t share the serial port in this way.
This is why
A workaround id to upload the sketch to the Uno then re-connect the ESP-01, but this means that you will have no serial monitor for debugging.
Have you ever tried to upload a sketch to the ESP-01 from the Arduino IDE?
If so, you will have overwritten the factory AT firmware and this will need to be re-flashed to the ESP-01.
