Smart card with integrated circuit

摘要

The chip card has a control unit in the form of a microprocessor and at least one memory with a number of memory locations accessible via addresses. The microprocessor contains several registers, at least one PSW register contg. a program status with a mode bit word defining a user mode or system mode. Access to at least part of the PSW register and to all such registers and to memory segments which are only used in system mode is blocked for a mode bit giving user mode.