Espressif Systems ESP User Manual

Chapter 4. Software framework
4.7.2 Is it possible to encrypt rmware for ESP8285?
• No, the ESP8285 chip does not support 󰝘rmware encryption function.
• Both ESP32 and ESP32-S2 support 󰝘rmware encryption, thus can be your substitution.
• If you insist on using ESP8285, you can achieve data encryption by adding an encrypted chip externally.
4.7.3 What is the dierence between secure boot v1 and v2?
Compared with secure boot v1, secure boot v2 has the following improvements: - The bootloader and
app use the same signature format. - The bootloader and app use the same signing key.
Currently, secure boot v1 is only reommended for earlier versions than ESP32 v3.0. For ESP32 v3.0
and later versions, ESP32-C3, ESP32-S2, and ESP32-S3, it is recommended to use secure boot v2.
4.7.4 After enabling secure boot, there is a build error indicating missing les. What
could be the reasons？
Error log: /Make󰝘le.projbuild:7/f/ESP32Root/secure_boot_signing_key.pem
Reason: security boot is a function for 󰝘rmware signature veri󰝘cation, which requires generating key
pairs. - For the method of generating a key pair when secure boot v1 is enabled, please refer to secure
boot v1 key generation. - For the method of generating a key pair when secure boot v2 is enabled, please
refer to secure boot v2 key generation.
4.7.5 After enabling secure boot, is it possible for modules to be ashed again?
• If the secure boot v1 is con󰝘gured as one-time, then it can only be 󰝙ashed once and the bootloader 󰝘rmware
cannot be re󰝙ashed.
• If the secure boot v1 is con󰝘gured as re󰝙ashable, then the bootloader 󰝘rmware can be 󰝙ashed again.
• The secure boot v2 allows re󰝙ashing the bootloader and app 󰝘rmware.
4.7.6 With ash encryption enabled, a module reports an error as flash read error
after reashed. How to resolve such issue?
With 󰝙ash encryption enabled, the module will not support plaintext 󰝘rmware 󰝙ash. For common fail-
ures, please refer to Possible Failures. You can use the espefuse script to disable the encryption and then
re󰝙ash the plaintext 󰝘rmware, or directly 󰝙ash the encrypted 󰝘rmware to devices referring to the 󰝙ash
encryption example.
Note: Please note there is a time limit for the 󰝙ash encrypted function.
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Espressif Systems ESP Specifications

General

Brand	Espressif Systems
Model	ESP
Category	Motherboard
Language	English