Secure execution process for code commands on data carrier involves forming reference check value as command is carried out and comparison value subsequently

摘要

The secure execution process for the commands of a program code (8) on a data carrier includes forming a reference checking value (10) and a comparison checking value (11) from at least one command, and checking one against the other. The reference check value is formed as the command is carried out, and the comparison check value is formed when a preset event occurs after the formation of the reference checking value.