| 摘要 |
Protective circuit according to Patent Claim 1 of P 3533787.7, for application to protection of information data contained in the target memory, which is a working memory divided into memory areas. At every memory access of an arithmetic unit, an access test unit (11) tests whether a new memory area is being addressed, and if there is access to a new area, arranges that the preamble of this area, which contains the vector, is fed to the comparator (1), to compare the key data with the identification, so that if the result of the comparison is positive, the vector is taken from the intermediate memory (4) and passed to the accessing arithmetic unit. Preferably, an identification of the previous area is stored in another intermediate memory (13), and is compared to an area connector which is contained in the preamble by a further comparator (14) when the new area is accessed, before the protective circuit is activated by the triggering logic (2). With this protective circuit, the provided programs are automatically forced on the accessing user, so that he or she cannot evade the protective measures. <IMAGE>
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