This tool is used to install firmware onto ESP-XX modules.

sudo apt-get install python3-serial python3-pip
sudo mv /usr/lib/python3.11/EXTERNALLY-MANAGED /usr/lib/python3.11/EXTERNALLY-MANAGED.bak
pip3 install esptool

3V3 UART       ESP-XX   ESP-01
========       ======   ======
3V3 ---------- VDD      8   21
3V3 -- 10K --- CHIP_EN  4   43
GND ---------- GND      1   65
                            87
RX  -- 390R -- U0TXD    2
TX  -- 390R -- U0RXD    7

RTS -- 390R -- EXT_RSTB 6
DTR -- 390R -- GPIO0    5

Use resistors for protection against mis-wiring.

$ esptool.py -p /dev/ttyUSB0 read_mac
esptool.py v2.0-beta2
Connecting....
Detecting chip type... ESP8266
Uploading stub...
Running stub...
Stub running...
MAC: 18:fe:34:XX:XX:XX
Hard resetting...