How to extract code on one DT-06 board to another board?
Okay. I found a way to extract the binary file (stock firmware) from one DT-06 and flash it to another modified DT-06, by using esptool command
/*To extract firmware */:
esptool.py -p COM4 -b 460800 read_flash 0 0x400000 dt06_backup.bin
/*To flash the backup binary file to another DT-06 */
esptool.py -p com4 write_flash -fm dout 0x00000 dt06_backup.bin