Modified interface with password-protected memory access with memory erasure when memory is accessed

摘要

The invention relates to a device in the form of an electronic circuit with a computer system and an interface. The device has a protected memory area which can be accessed via the interface in a first and second access method. The interface has a first customer password register (CPWR) and a second customer password register (CPWR) as well as a password register (PWR). The first customer password register (CPWR) contains a first customer password. The second customer password register (CPWR) contains a second customer password. The password register (PWR) can be written with a password using the interface. Access to the protected memory area in a first type of access is only possible if the first customer password in the first customer password register (CPWR) matches the password in the password register (PWR) in a predetermined manner. Access to the protected memory area in a second type of access is only possible if the customer password in the first customer password register (CPWR) matches the password in the password register (PWR) in a predetermined manner. The first type of access and the second type of access are different. When the protected memory area is accessed using the first type of access, the logical content of the protected memory area is reset or deleted before or immediately when access is enabled. In addition, the customer password registers are protected against manipulation.