• All synchronization has to be made outside the TMR region, because asynchronous interfaces inside the TMR region can result in a one cycle jitter of the synchronized signal, which would lead to a comparison error.
• Recovery needs the complete state of all IP cores to be restored.
• All IP cores need to have the identical configuration as their triplicated counterparts.
It might not be possible to include IP cores or RTL modules that do not adhere to these rules in the TMR subsystem. In this case, third-party tools such as the BL-TMR Tool [Ref 16] might be used to implement fine-grained majority voting for these cores or modules.