1. A method of recording and carrying out microprograms in a processor associated with a data processing system in which a microprogram recorded in a read/write store belonging to the processor contains microinstructions which are to be carried out sequentially with the aid of a data table store, comprising the steps of: providing a storage location for a parametered microinstruction containing a first parameter and a second parameter at a predetermined address in the read/write store; storing in the data table store a first value corresponding to the first parameter and a second value corresponding to the second parameter; combining the first and second values extracted from the data table store to form a calculated microinstruction; storing the calculated microinstruction in the read/write store at the predetermined address; and executing the calculated microinstruction.