C.1.2. Configuring little or big-endian operation

The Integrator/CP can be configured to operate as a big-endian or little-endian system. To change to big-endian operation, write to the appropriate register in CP15 on the ARM core.


The CP15 register is not present in the ARM7TDMI and systems CP systems using this processor must use a Core Tile signal to switch to big-endian mode.

The IM-LT3 FPGA image for use with the CT7TDMI is little-endian. The image must be rebuilt if big-endian operation is required. The big-endian image drives a signal to the Core Tile that selects big-endian mode.

There is a delay between changing the endian configuration of the core and the system functioning in the new endian mode. Changing endianess must only be done at the start of a debugging session. The change must have taken effect before you can perform any subword accesses.


The Integrator/CP display system and Ethernet controller cannot operate in big-endian mode.

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