Crack MCU code is a very important step for reverse engineering microcontroller. As we all know, most of mcus have embedded code in the flash or eeprom area. In order to recover the lost file or clone the obsolete electronic product, mcu code crackion could always be a necessary step. But mcu manufacturers will commit their best to prevent the P89LPC908 mcu code cracking from their mcus.
The most commonly used way to avoid mcu code crackion is encrypt their code. However, mcu should also emphasis on the secret key management and storage. If the secret key is programmable or able to modify optional, which is quite similar to situation compare with the code stored in the EEPROM of mcu. Store those plain information inside the programmable memorizer could be a great threat to the mcu security against retrieving microcontroller pic32mx440f128H .
Semi-invasive mcu code crackion and faulty injection mcu code crackion, which cause danger to hardware security on the mcu chip, so manufacturer need to research and develop some methods to stop mcu S3F94C8 code unlocking. We can use Self-timed dual-rail circuit design technology, then the logic sequence “1” or “0” won’t be used as high or low electrical level on the single line, but “HL” or “LH” on a pair of line. The composited signals “HH” can generate the alarm when crack mcu code, which will finally lead to processor reset. Circuit can be designed into a system which won’t have failure even if single transistor failure. This technology can increase the mcu code cracking difficulty when use power consumption analysis. Of course, attacker need to balance the security level and spending on the protection technology.
In the old days when 8031 series mcu being applied, designer cann’t help but expand ROM or RAM, at that time, address line and data line have been used for crossing technology which cause the swicthing of double digitals or more digitals line which require to use them simutaneouly when layout printed circuit board and write a programme to prevent mcu code crackion.