It is powered by a 3.3V power supply that I bought just for this project.
Its TX and RX are connected to RX and TX on the Arduino Uno via a level shifter board.
ESP-01 TX <---- L level shifter board H ----> TX
ESP-01 RX <---- L level shifter board H ----> RX
The Arduino Uno is running an "empty" sketch.
I have the Serial Monitor on the Arduino Uno set to 115200 with CR.
When power is first applied, the blue LED on the ESP-01 briefly flickers.
The red LED is on.
I see some strange characters in the Serial Monitor, and then
Ai-Thinker Technology Co., Ltd.
ready
The ESP-01 is alive and my smartphone says that it is AI-THINKER_D1E42E
But the module doesn't respond to AT.
I tried all the baud rates from 9600 to 115200.
Any ideas?