I was digging around in my parts and found an old ESP32 Thing that I had never used. I plug it in and it shows up on COM6 as a FTDI device.
Compile and Flash code with VSCode with ESP-IDF, but it fails with:
Failed to connect to ESP32: Wrong boot mode detected (0x13)! The chip needs to be in download mode.
This is encouraging, but I’ve done BOOT + RST buttons and that’s no help. I should also note that a blue LED on the board is flashing about once per second - I assume this is the default program it was shipped with?
This is probably the first ESP32 dev board shipped by Sparkfun, so I don’t have much hope of help. But maybe someone has an idea?
depending on the board you have, make sure to press RST and BOOT or O button together. Release the RST, but keep BOOT or 0 button pressed until uploading has started.
Your solution works. With newer ESP32 dev boards (S3 and C6) I do not have to hold down BOOT until uploading starts, I just have to hold down BOOT, press/release RESET, then release BOOT. Why does this old dev board require me to hold down BOOT?
Then I get these messages:
load:0x3fff0030,len:6276
load:0x40078000,len:15716
load:0x40080400,len:4
— 0x40080400: _init at ??:?
ho 8 tail 4 room 4
load:0x40080404,len:3860
entry 0x4008063c
W (65) rtc_clk_init: Possibly invalid CONFIG_XTAL_FREQ setting (40MHz). Detected 26MHz.
Unfortunately after that point the terminal shows garbage characters, such as:
?�
��������
�r���ܒ��
And the connected ePaper display does not work. I’ll have to ry another ESP32 from my junk box.
Why does this old dev board require me to hold down BOOT?
To put the ESP32 version of that time in boot mode. It will then accept a new upload. Make sure to keep BOOT pressed until the uploading has started (showing the % uploaded)
the terminal shows garbage characters
Maybe the speed in the sketch is different than the monitor. Maybe you have the incorrect ESP32 selected.