Boot Problems

[storchalberto]

I am using a D1 Mini ESP32 ESP-32 WiFi+Bluetooth Internet of Things Development Board based ESP8266 Fully Functional,
connected to a MAX98357A module and a Youmile SD Card Module Micro SD SDHC TF Card Adapter Reader Module
This is my configuration (and connections):
GPIO04 I2S DOUT
GPIO05 I2S BCLK
GPIO12 SPI MISO
GPIO13 SPI CLK
GPIO14 SPI MOSI
GPIO15 SDCArd Select
GPIO16 I2S WS
At the power on or after an HW reset, the device do not start correctly and i see on the serial port continously:

rst:0x1 (POWERON_RESET),boot:0x33 (SPI_FAST_FLASH_BOOT)
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff
invalid header: 0xffffffff

If i disonnect the power of the SDcard reader, and start the system,the device start normally and is capable to,
play audio files, but cannot see the SD card (obviously).
At this time if i reconnect the power of the SDcard reader and do the command Restart 1 on the serial port,
the device start correctly and i can see the sd card and play the files on the sd card.
Any suggestion?

[Noschvie]

Can you rule out a problem with the power supply?

[storchalberto]

The power supply is my PC USB 3.0. The sdcard reader use the 3.3V of the ESP32 Board and wen started using the metodology i say, there are no problems accessing the sd card.

[sfromis]

Using the PC USB will often mean that you increase your risk of lacking power.

Not clear what you hardware setup is, you mention both ESP32 and ESP8266.

Those invalid header: 0xffffffff could suggest not having flashed a build on that MCU.

[storchalberto]

the board is a I am using a D1 Mini ESP32. i have flashed the build on the MCU, due for the fact that if i disonnect the power of the sd module, the system runs correctly. As i said, if i reconnect the power and use the command restart 1, all runs correctly (i see the sdcard). but if i push the reset button on the board, i see the problem. during the continuous signallin of the problem on the serial consolle, if i disconnect the power of the sd card, the system starts correctly, but obviously i not see the sd card.it seems that there is a problem in the startup during the initialization of the sd module. there is a way to start the system without the initialization of the sd card and initialize the card later.

[Staars]

Can you try your setup without using strapping pins, which in your case are GPIO 12 (must be LOW during boot) and
GPIO 15 (must be HIGH during boot)?

[storchalberto]

OK: the problem is on the GPIO12. I have used GPIO39 as MISO and now i do not have problem at boot. the SDCard CS on GPIO15 has no influence. Thanks