What is MCU decryption?

What is MCU decryption?

Microcontroller Units (MCUs) usually have internal EEPROM/FLASH, where users can store programs and working data. What is MCU decryption? If you want to read the programs inside, you must unlock the password to read them. This process is usually called MCU decryption or chip decryption.

To prevent unauthorized access or copying of the internal programs of MCUs, most MCUs have encryption lock bits or encryption bytes to protect the internal programs. If the encryption lock bits are used (locked) during the programming process, the internal programs of the MCUs cannot be directly read by ordinary programmers. Attackers of MCUs use specialized equipment or self-made equipment, take advantage of loopholes in the design of MCU chips or software defects, and through various technical means, they can extract key information from the chips and obtain the internal programs of the MCUs, which is called MCU decryption. After the programs of most MCUs are written into the MCUs, in order to prevent others from illegally stealing them, engineers will encrypt them to prevent others from reading the programs.

The encryption of MCUs is divided into two types: hardware encryption and software encryption. For hardware encryption, as for MCUs, generally, MCU manufacturers will solidify the encryption fuses inside the Integrated Circuits (ICs). The fuses have an encrypted state and a non-encrypted state. In the encrypted state, ordinary tools cannot read the program content in the ICs. If it is necessary to read the content, it is related to hardware decryption, which requires professional hardware decryption tools and professional engineers.