Cannot program the board second time
Posted: Mon Sep 12, 2022 12:38 pm
Hi,
I designed custom board using ESP32-WROOM-32U-N16. I connected UART communication to the external programmers (to save space on the board) I also connected IO0 to switch to pull it to the GND (as said in data sheet). I also made EN pin high with 10 k resistor and 0.1 uF capacitor. I can successfully connect it and program it first time (I am using esp-mdf) and after that I can just open serial monitor and check logs etc but I just cannot program it again. I get this: "A fatal error occurred: Failed to connect to ESP32: Invalid head of packet (0x49)" and head of packet is always different and I still push IO0 to the GND to enable UART programming but it just do not work. I do not know what am I doing wrong.
I designed custom board using ESP32-WROOM-32U-N16. I connected UART communication to the external programmers (to save space on the board) I also connected IO0 to switch to pull it to the GND (as said in data sheet). I also made EN pin high with 10 k resistor and 0.1 uF capacitor. I can successfully connect it and program it first time (I am using esp-mdf) and after that I can just open serial monitor and check logs etc but I just cannot program it again. I get this: "A fatal error occurred: Failed to connect to ESP32: Invalid head of packet (0x49)" and head of packet is always different and I still push IO0 to the GND to enable UART programming but it just do not work. I do not know what am I doing wrong.