PURPOSE: To pack program data into hardware with no generation of undesired address by judging whether each block of program data is packed or not based on the selection data when the program data is packed.

CONSTITUTION: At start-up of a system an active output signal is transmitted from a counter 21A and at the same time an initial address '0000' is loaded. Thus a flag extracting part extracts the selection data '0' out of an address 0 of a selection data storing means 1 and outputs the data '0' to a reading part 21 and an output part 23 respectively. Then the counter 21A is reset owing to a fact that the selection data is equal to '0' and '1000' is loaded. A flag extracting part 22 extracts the selection data '1' on an address '1' out of the means 1 and outputs the data '1'. Thus the output of the selection data is confirmed. Then a reading part 21 loads the initial address '1000' owing to a fact that the selection data is equal to '1'. Then the head of a program 13 is packed into hardware.