1. A method for operating a processor having an array of data processing cells controlled by a controlling unit, the method comprising: a data processing cell sending a trigger to the controlling unit upon finishing a current data processing operation; in response to receiving trigger, the controlling unit supplying one or more new processing instructions to the processing cell sending the trigger while the other cells continue processing using a current set of one or more processing instructions, and in response to receiving said one or more new processing instructions, the receiving data processing cells processing data using the one or more new processing instructions.