ESP32-S2: Entering bootloader from FW using RTC memory magic number

[jonspieg]

Operating System

Windows 10

INFO_UF2.TXT

not relevant

What happened ?

I have a custom board that implements the esp32-s2 solo module.
I've attempted resetting the board into bootloader mode using the following snippet from the readme:
`#include "esp_private/system_internal.h"
void reboot_to_uf2(void)
{
// Check out esp_reset_reason_t for other Espressif pre-defined values
enum { APP_REQUEST_UF2_RESET_HINT = 0x11F2 };

// call esp_reset_reason() is required for idf.py to properly links esp_reset_reason_set_hint()
(void) esp_reset_reason();
esp_reset_reason_set_hint(APP_REQUEST_UF2_RESET_HINT);
esp_restart();
}`

This worked perfectly when compiled by the Arduino IDE.
However, when I used platformio with the same code, it just went into reset loop.

There was a very slight difference in the boot messages the chip spits out from uart0:
from arduino ide it was "rst:0x3 (RTC_SW_SYS_RST),boot:0x8 (SPI_FAST_FLASH_BOOT)"
from platformio it was "rst:0xc (RTC_SW_CPU_RST),boot:0xa (SPI_FAST_FLASH_BOOT)"

this might be related, or it might be irrelevant.

How to reproduce ?

flash example code using platformio on an esp32-s2 dev board

Debug Log

No response

Screenshots

No response

[hathach]

Closed since clearly not a bug of this repo. Check your flashing scheme, layout, linking etc of platformio and arduino

[jonspieg]

Indeed not a bug in this repo, but I wonder how the compiler/linker settings has anything to do with this feature.
I'm going to dive deeper into how platformio are handling the compilation and upload.

do you maybe have an idea what could be the culprit?

Thanks

[hathach]

it can be anything, I don't use PIO to give an advise. For further question, please post on Adafruit support forum. Github is mostly for code related issue.