May 2006, Issue 190

Mobile Phone Book
M16C/62P-Based Data Backup System
Renesas M16C 2005 Honorable Mention

PHONE BOOK

The EF with ID 6F 3A, which is also known as the abbreviated dialing number (ADN) file, is responsible for storing all of the names and phone numbers in the SIM smart card. To select it, you must select first the DF Telecom with ID 7F 10. The phone book is a linear record file of variable length. The record length can be obtained by querying for the first record with length 0x00: A0 B2 01 04 00. The SIM smart card answers with status words 67 XX, where XX is the length of the record used in the phone book.

The structure of every phone record includes several fields. The Name field contains alpha tagging of the associated dialing number. It’s coded in ASCII with the most significant bit set to zero. All of the unused bytes are set to 0xFF.

The Length field contains the length of the BCD dialing number. The type of number (TON) field distinguishes between national and international phone numbers. The typical values are 0x81 for national phone numbers and 0x91 for international phone numbers. The Dialing Number field contains the dialing number coded in BCD with the least significant digit in the first place in every BCD digit.