14.4. DCode bus interface

The DCode interface is a 32-bit AHB-Lite bus. Data and debug accesses to Code memory space (0x00000000 - 0x1FFFFFFF) are performed over this bus. Core data accesses have a higher priority than debug accesses. This means that debug accesses are waited until core accesses have completed when there are simultaneous core and debug access to this bus.

Control logic in this interface converts unaligned data and debug accesses into two or three (depending on the size and alignment of the unaligned access) aligned accesses. This stalls any subsequent data or debug access until the unaligned access has completed.

See Access alignment for a description of unaligned accesses.

Note

It is strongly recommended that any external arbitration between the I-Code and D-Code AHB bus interfaces ensures that D-Code has a higher priority than I-Code.

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