Wincor Nixdorf CMD-V5, Service Manual

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Service functionings Introduction
1-22
Cash Media Dispenser Version 5 - Service Manual 01750214538 A
Handling the TPM
BIOS setting
When the PC leaves the factory, the TPM chip is in the "Enabled and
Activated" state.
Any change in this status (in the BIOS as well as via the Infineon Professional
package) will cause the deletion of the secret key in the TPM, so that the PC is
no longer usable for capacity protection between RM3 and system PC. A
change of this status can also occur if the TPM itself assumes that it is under
attack and deletes its content for security reasons.
If someone deactivates or clears the TPM and reactivates it afterwards, a
secret key will again be in the TPM, but this one will no longer match the
certificates in the flash memory of the system board. A check to see whether
the key is still correct can currently only take place at the time of the initial
operation of the component with the safe channel.