公开(公告)号：JPH07147613A

公开(公告)日：1995-06-06

申请号：JP14643694

申请日：1994-06-28

Applicant: KOREA ELECTRONICS TELECOMM

Inventor： KEN YOSHIHIRO ,  KIN ROUKOU ,  JIN HEIKIYOKU

IPC: G06K19/07 ,  G06K19/00 ,  G06K19/073 ,  G07F7/00 ,  G07F7/08 ,  H04M15/00 ,  H04M17/00

Abstract: PURPOSE: To prevent the increase of the usable amount of the user of a prepaid card used for card type public telephone sets and, at the same time, to minimize the capacity of a memory which stores the usable amount. CONSTITUTION: A prepaid integrated circuit card is provided with a control section 20 which makes an input-output section 10 receive a new usable amount and instruction words for communication from a public telephone set 50 and discriminates whether or not an instruction word for communication received by means of the section 10 is the updating instruction of the usable amount stored in a memory 40. The control section 20 makes a comparator 30 compare the usable amount stored in the memory 40 with the new usable amount and controls the updating of the usable amount stored in the memory 40 based on the compared results.