4

AT88SC0404CRF

5023CS–CRRF–12/06

User Memory

The EEPROM user memory is divided into four user zones as shown in the memory

map in Table 1. Multiple zones allow for different types of data or files to be stored in

different zones. Access to the user zones is allowed only after security requirements

have been met. These security requirements are defined by the user in the configuration

memory during personalization of the device. The EEPROM memory page length is 16

bytes.

Configuration

Memory

The configuration memory consists of 2048 bits of EEPROM memory used for storing

system data, passwords, keys, codes, and security-level definitions for each user zone.

Access rights to the configuration zone are defined in the control logic and may not be

altered by the user. These access rights include the ability to program certain portions of

the configuration memory and then lock the data written through use of the security

fuses.

Security Fuses

There are three fuses on the device that must be blown during the device personaliza-

tion process. Each fuse locks certain portions of the configuration memory as OTP

memory. Fuses are designated for the module manufacturer, card manufacturer and

card issuer and must be blown in sequence.

Table 1. Memory Map

Zone

$0

$1

$2

$3

$4

$5

$6

$7

User 0

$00

–

128 Bytes

–

$78

User 1

$00

–

128 Bytes

–

$78

User 2

$00

–

128 Bytes

–

$78

User 3

$00

–

128 Bytes

–

$78