Datasheet

3.2.4. Delay Circuit
The delay circuit of ESP-Prog includes the bus buffer, inverter, MOS tube, first-order RC circuit, and
other components. This delay circuit ensures that the ESP32 chip can power up or reset itself, before
connecting with the JTAG signal, thus protecting the chip from the influence of JTAG on power-up or
reset.
3.2.5. LED Status Indication
The red LED lights up when the system is connected to the 3.3V power;
The green LED lights up when ESP-Prog is downloading data to ESP32;
The blue LED lights up when ESP-Prog is receiving data from ESP32.
3.2.6. Pin Headers
Users can choose either the 3.3V or 5V power supply for the Program and JTAG interfaces, using the
pin headers shown in the figure below.