PURPOSE: To write a code number surely without providing a special write means, by calling out a code input routine by a switch operation and writing in a code number transmitted from a service station at the center on request at a remote location to a memory.

CONSTITUTION: A facsimile 21 is connected to an exchanger 25 via a telephone line 26 via a telephone set 21a and a telephone set 21a is connected to a central facsimile 22 from the facsimile 21 via this exchanger 25. A facsimile 22 is provided with an operation key 24, and the data inputted from the key 24 is displayed on a display device 23. When the code number of itself is written in an erasable programmable memory 16 with the facsimile 21, a mode switch 5 connected to a microcomputer CPU18 is operated and the discriminated code routine is called out for the erasable programmable memory 17. According to this routine, the code number transmitted from the facsimile 22 is stored in the memory 16 via a write circuit 19.