2.7.7. Access types for address range comparators

If you are using two address comparators as an address range comparator, the access type must be identical for each, otherwise the behavior of the comparator is unpredictable. The only exceptions to this are:


This information is also included in About the address comparator registers.

Selecting a range to include address 0xFFFFFFFF

Ranges are defined to be exclusive of the upper address, so if you specify an upper address of 0xFFFFFFFF, only addresses up to and including 0xFFFFFFFE match. To specify a data address to include 0xFFFFFFFF, configure the upper address comparator as follows:

  • Value Register = 0xFFFFFFFF

  • set Access Type Register bits [4:3] (size mask) to b11.

This is the only case where the size mask can be different between the two address comparators of an address range comparator.

For more information, see Address range comparators.

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