Espressif Systems ESP - 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? . . . . . . . . . . . . . . . . . . . . . . . 106
4.7.12 Can the secure boot function be enabled for ESP32 in Arduino development environment? 106
4.7.13 What are the use scenarios for secure boot and 󰝙ash encryption? . . . . . . . . . . . . . . 107
4.7.14 What are the data stored in eFuse involved in secure boot and 󰝙ash encryption? . . . . . . 107
4.7.15 Enabling secure boot failed with the log “Checksum failure”. How to 󰝘x it? . . . . . . 107
4.7.16 NVS encryption failed to start and an error occurred as nvs: Failed to read NVS
security cfg: [0x1117] (ESP_ERR_NVS_CORRUPT_KEY_PART). How
can I solve this issue? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
4.7.17 After 󰝙ash 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? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
4.7.18 Why is reltead data not encrypted after I enable CONFIG_EFUSE_VIRTUAL and 󰝙ash
encryption? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
4.7.19 Can I update an app 󰝘rmware which enables 󰝙ash encryption in a device which does not
enable fash encryption through OTA? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
4.7.20 How can I delete keys of secure boot? . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
4.7.21 After I enabled secure boot or 󰝙ash encryption (development mode), I cannot 󰝙ash the new
󰝘rmware, and an error occured as Failed to enter Flash download mode.
How can I solve this issue? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
4.7.22 After I input the command espefuse.py read_protect_efuse BLOCK3
command in the terminal con󰝘gured 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?
. . . . . . . . . . . . . . 108
4.7.23 How can I enable secure boot or 󰝙ash encryption by pre-burning eFuse? . . . . . . . . . . 108
4.7.24 After enabling Secure Boot, why can’t I 󰝙ash the new bootloader.bin using the idf.py build
command? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
4.7.25 After enabling Secure Boot or 󰝙ash encryption, how can I view the security-related infor-
mation in the device? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
4.7.26 After enabling Secure Boot or 󰝙ash encryption, what should I pay attention to during OTA
(Over-The-Air) updates? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
4.8 Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
4.8.1 FAT Filesystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
4.8.2 Non-Volatile Storage (NVS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
4.8.3 PSRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
4.8.4 SD/SDIO/MMC Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
4.8.5 SPI Flash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
4.8.6 SPIFFS Filesystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
4.8.7 Other Storages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
4.9 System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
4.9.1 My application does not really need the watchdog timer, can I disable it? . . . . . . . . . . 117
4.9.2 What are the di󰝗erences between RTOS SDK and Non-OS SDK? . . . . . . . . . . . . . 117
4.9.3 Why does the log output ets_main.c when ESP8266 starts? . . . . . . . . . . . . . . . . 117
4.9.4 Why do I get compile errors when using IRAM_ATTR in Non-OS SDK? . . . . . . . . . 117
4.9.5 Where is main function in ESP8266? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
4.9.6 Which part of ESP8266 partition-tables should be paid special attention to? . . . . . . . . 118
4.9.7 Is it possible to compile the binaries in application layer and bottom layer separately? . . . 118
4.9.8 How can I to reduce the IRAM occupied by the ESP32 system? . . . . . . . . . . . . . . 118
4.9.9 How can I optimize the size of binary 󰝘les compiled by ESP32? . . . . . . . . . . . . . . 118
4.9.10 How can I turn o󰝗 log output in ESP32？ . . . . . . . . . . . . . . . . . . . . . . . . . 118
4.9.11 How to modify the GPIO used for log output on ESP32? . . . . . . . . . . . . . . . . . . 118
4.9.12 When ESP8266 is in Deep sleep mode, can the data stored in RTC Memory work? . . . . 119
4.9.13 What is the maximum length of the NVS Key for ESP32? . . . . . . . . . . . . . . . . . 119
4.9.14 Does the cJSON in ESP-IDF release/v4.2 support uint64_t data analysis? . . . . . . . . . 119
4.9.15 Given that the GDB debugging function is working before the 󰝙ash encryption is disabled,
then why does the device keeps restarting during the GDB debugging after the 󰝙ash en-
cryption is enabled? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
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