2.2.2. Priority

The priority of a region is fixed and is determined by the region number. Figure 2.3 shows how the priority of a region increases with the region number.

Figure 2.3. Region priority

When a transaction is received, its address is checked for a match with all the configured regions in turn. The order in which the regions are checked is determined by the priority level, the highest priority level is first. The first region that matches the transaction address match is used as the matching region. The matching regions security permission determines whether the transaction is permitted.

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