A device has a cache memory for temporarily storing contents of a buffer memory. The device has a mirror unit coupled between the cache memory and the buffer memory. The mirror unit is arranged for providing at least two buffer mirrors at respective different buffer mirror address ranges in the main address range by adapting the memory addressing. Due to the virtual mirrors data on a respective address in any of the respective different buffer mirror address ranges is the data of the buffer memory at a corresponding address in the buffer address range. The device enables processing of a subsequent set of data in the buffer memory via the cache memory without invalidating the cache by switching to a different buffer mirror.