Espressif Systems ESP Faq page 10

4.7.11 After GPIO0 is pulled down, the ESP32 cannot enter download mode and prints " download
mode is disable". What could be the reason?
4.7.12 Can the secure boot function be enabled for ESP32 in Arduino development environment?
4.7.13 What are the use scenarios for secure boot and flash encryption?
4.7.14 What are the data stored in eFuse involved in secure boot and flash encryption?
4.7.15 Enabling secure boot failed with the log "Checksum failure". How to fix it?
4.7.16 NVS encryption failed to start and an error occurred as nvs: Failed to read NVS
security cfg:
can I solve this issue?
4.7.17 After flash encryption was enabled, a warning occurred as esp_image: image at
0x520000 has invalid magic byte (nothing flashed here). How
can I solve this issue?
4.7.18 Why is reltead data not encrypted after I enable CONFIG_EFUSE_VIRTUAL and flash
encryption?
4.7.19 Can I update an app firmware which enables flash encryption in a device which does not
enable fash encryption through OTA?
4.7.20 How can I delete keys of secure boot?
4.7.21 After I enabled secure boot or flash encryption (development mode), I cannot flash the new
firmware, and an error occured as Failed to enter Flash download mode.
How can I solve this issue?
4.7.22 After I input the command espefuse.py
command in the terminal configured with ESP-IDF to enable the read-protection
for Efuse BLOCK3, why is the data of the Efuse BLOCK3 all 0x00 when I input
esp_efuse_read_block() to read the Efuse BLOCK3?
4.7.23 How can I enable secure boot or flash encryption by pre-burning eFuse?
4.7.24 After enabling Secure Boot, why can' t I flash the new bootloader.bin using the idf.py build
command?
4.7.25 After enabling Secure Boot or flash encryption, how can I view the security-related infor-
mation in the device?
4.7.26 After enabling Secure Boot or flash encryption, what should I pay attention to during OTA
(Over-The-Air) updates?
4.8 Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
4.8.1 FAT Filesystem
4.8.2 Non-Volatile Storage (NVS)
4.8.3 PSRAM
4.8.4 SD/SDIO/MMC Driver
4.8.5 SPI Flash
4.8.6 SPIFFS Filesystem
4.8.7 Other Storages
4.9 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
4.9.1 My application does not really need the watchdog timer, can I disable it?
4.9.2 What are the differences between RTOS SDK and Non-OS SDK?
4.9.3 Why does the log output ets_main.c when ESP8266 starts?
4.9.4 Why do I get compile errors when using IRAM_ATTR in Non-OS SDK?
4.9.5 Where is main function in ESP8266?
4.9.6 Which part of ESP8266 partition-tables should be paid special attention to?
4.9.7 Is it possible to compile the binaries in application layer and bottom layer separately?
4.9.8 How can I to reduce the IRAM occupied by the ESP32 system?
4.9.9 How can I optimize the size of binary files compiled by ESP32?
4.9.10 How can I turn off log output in ESP32？
4.9.11 How to modify the GPIO used for log output on ESP32?
4.9.12 When ESP8266 is in Deep sleep mode, can the data stored in RTC Memory work?
4.9.13 What is the maximum length of the NVS Key for ESP32?
4.9.14 Does the cJSON in ESP-IDF release/v4.2 support uint64_t data analysis?
4.9.15 Given that the GDB debugging function is working before the flash encryption is disabled,
then why does the device keeps restarting during the GDB debugging after the flash en-
cryption is enabled?
[0x1117] (ESP_ERR_NVS_CORRUPT_KEY_PART). How
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read_protect_efuse
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BLOCK3
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