ESP32 Forum

Hi Folks,

I get this "flash read err, 1000; Falling back ...." error in all the programs I tested so far.
This only happens when I hard reset the esp32 module or after wakeup from deep sleep.
After the error there is a another reset and everything seems to work normally.
This error is not issued after the reset after flash.

I checked similar threads, but could not find a definitive answer.
Bootloader is at 0x1000 and encryption is not enabled.

Any ideas? Should I ignore it?

Thanks in advance


------------------------- Manual reset
rst:0x1 (POWERON_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
flash read err, 1000
Falling back to built-in command interpreter.
OK
>ets Jun 8 2016 00:22:57

rst:0x10 (RTCWDT_RTC_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee

------------------------- Deep sleep reset
rst:0x5 (DEEPSLEEP_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
flash read err, 1000
Falling back to built-in command interpreter.
OK
>ets Jun 8 2016 00:22:57

rst:0x7 (TG0WDT_SYS_RESET),boot:0x13 (SPI_FAST_FLASH_BOOT)
configsip: 0, SPIWP:0xee

I had this when I had set the crystal frequency incorrectly, and the flash clock speed was too high for the SPI flash chip. I'd suggest trying to use a slow speed flash SPI bus in DIO mode.

Hi,

I tried both 26 and 20 MHz but did not help, thanks anyway.

Friends question is still pending.

Cheers

I'm having the same exact issue. I'm using a button reset for deep sleep mode, and if pressed for a short second the device will get the 0x1000 flash error, but if I hold down the button it will first get the 0x1000 error but then properly wake from deep sleep mode after resetting . Hopefully this helps.

As a matter of fact my situation is the same. My question is can we ignore the error message.

It depends on what you want you are trying to do. When you get the 0x1000 Flash error, the chip will reset, so you lose any data you were trying to store. If this isn't an issue, then yeah you can ignore it.

Thanks for the comment, cheers

hakkig wrote: This only happens when I hard reset the esp32 module or after wakeup from deep sleep.
After the error there is a another reset and everything seems to work normally.

Some flash chips can take longer than expected to power on, so the first read (after the bootloader starts) sees invalid flash. This problem may be more prominent on some hardware board designs (power decoupling, etc).

There is a config option in ESP-IDF to avoid this problem when waking from deep sleep, by adding a small delay before normal booting resumes. By default on recent IDF this is set to 2ms, which was long enough for all the flash chips we tested, but you may want to try setting it higher:
http://esp-idf.readthedocs.io/en/latest ... keup-delay

Angus

Hi, thanks
I tested with 3000, 5000 and then 500 uS but the result is the same.
Maybe my board is faulty, I will order and test with a new one.

Cheers