ESP-01 FROM LCTECH RELAY - Cant get into bootloader mode to flash

[salatiel]

Hello, I have bought a few relays from Aliexpress. Those come with one ESP-01 ( not esp-01s).
I have a usb-ttl adapter made for flash those little esp chips and has a button to toggle the bootloader mode.
In all other esp-01 or esp01-s i have, i can easily toggle bootloader mode and flash tasmota or anything else, but in these specific esp-01 that came with these relays I just can not make tasmota or esptool detect them.

The red light on the esp01 is always on, nothing else.

Code: Select all

esptool.py v4.7.0
Serial port /dev/ttyUSB0
Connecting......................................

A fatal error occurred: Failed to connect to ESP8266: No serial data received.
For troubleshooting steps visit: https://docs.espressif.com/projects/esptool/en/latest/troubleshooting.html

Has anyone come up with this kind of problem before ?

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[AgentSmithers]

Man does this bring back memories. You need to pull the en to ground if I recall upon boot. Then you should be able to access the SPI protocol to load the flash of the model.

The ESP-01 is just the model of the PCB board but its helpful to know the tracing to the esp8266 to then compare it to the product manual on what the proper procedure is to kick it into flash mode to then load it from w.e tool your using.

Considering the pin layout you cant plug this into a breadboard directly, but you can run 8 individual wires from it into a line on the breadboard and ground the correct pins to kick it into the right mode to load the firmware.

Let me know if you have any other questions and I'll try to keep an eye out. I just loaded my esp8266 project up a few weeks ago myself as I had to power through the installer quite a bit to get it to fly again as the falcon open toolkit isn't maintained anymore. Hope your able to get this to fly.