ESPRESSIF
ESP32 firmware download (writing) failure - the first thing to check
DeviceIN
2023. 10. 31. 19:04
If firmware download (flashing) fails on ESP32, the first thing to check:
Rule #1: When you power on the ESP32, messages should appear on the firmware download port (UART0).
- UART0 should be properly connected to the PC, and when you power cycle the ESP32 module, you must see log messages. The baud rate should be 115200, and you can view the messages with a common serial terminal program (e.g., Tera Term, RealTerm, PuTTY, etc.).
- The messages can be reset messages or meaningless error messages, but something should be displayed. After that, analyze the messages to identify what went wrong and verify if everything is normal.
- These log messages will appear even if there is no firmware and even if the Flash memory itself is not connected.
Rule #2: If there are no messages as mentioned in Rule #1, it is 100% a hardware problem.
- In this case, you need to inspect external hardware factors such as circuitry, power, noise, USB-UART converter board status, PC status, cable condition, etc.
- It has nothing to do with the firmware or the flashing program.
