7.7. Static split/lock

Static split/lock enables you to choose between:

Because this is a static split/lock, you can only switch modes during reset. The global input SAFEMODE enables you to choose the mode:

The SAFEMODE input must be kept stable during normal operation and can only be changed at reset.

Figure 7.2 shows how split/lock is implemented.

In static split/lock, processor 1 is present with both noram and ram modules. When the processor is operating in lock-step mode, the ram logic is clamped.

The redundant no_cpu module, that is, SCU and AXIS, is always present but it is only used in lock-step mode. It is clamped in performance mode.


Only the processor 0 slave port of the SCU is duplicated. The interface with processor 1 is not required because, when in lock-step mode, the processor 1 noram is used as a redundancy of processor 0.

Figure 7.2. Static split/lock

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