ESP32 – flashing the chip

Once the ESP32 Toolchain is built, we’re ready to compile and flash the example program. This short tutorial shows how to compile and burn the code into ESP32.


Before compilation part we’re able to change menu options, i.e. we can configure the serial port to be used for uploading, etc. For the test, let’s compile blinky example from ESP-IDF.

cd $HOME/esp/esp-idf/examples/02_blink
make menuconfig

Flashing the ESP32

To flash the chip we need to wire up an external power supply (3.3V) that’s rated to a couple of hundred mA at least, USB-TTL converter (3.3V) and the ESP32. To put the chip in the bootloader mode, we need to hold the BOOT pin (GPIO0), grounded while grounding and releasing the RESET pin (EN). If we do this with a terminal application running (optional), we’ll see “waiting for download” typed out. We need to close terminal program before typing make flash. After flashing procedure we can re-open the terminal program and we should see lots of debugging info on start.

make flash


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