6

2035C–SMEM–6/08

AT88SC1003

6.

Memory Zones

Table 6-1.

Memory Zones

Zone

Definition

Fabrication Zone

FZ (16 bits)

The 16-bit fabrication zone is programmed when the chip is manufactured and cannot be changed.

Application software may check this fabrication zone code to assure that the device was

manufactured by Atmel.

Issuer Zone

IZ (64 bits)

The 64-bit issuer zone is programmed by the card issuer during the personalization phase. It will

contain issuer-specific information, such as serial numbers and dates. This area becomes read-only

after the issuer fuse has been blown. Read access is always allowed in the issuer zone.

Security Code

SC (16 bits)

The security code is initially set by Atmel to protect the product during transportation to the card

issuer. During personalization, this code must be entered and verified by the AT88SC1003 to allow

access to the

changed in either security mode. The security code gives access to Application Zones 1, 2, and 3,

and also gives access to the code-protected zone area for erase and write. Verification of the security

code will set the internal flag SV to “1”. Atmel ships the device with a security code (transportation

code) pre-programmed. This protects against the unauthorized use of an unpersonalized device, and

should be written to a new value during initialization.

Security Code Attempts

Counter SCAC

(4 bits plus 12 unused bits)

The protocol for verification of the security code requires that the user write one of the first four bits of

the SCAC to a logic “0”. This allows the SCAC to count the number of consecutive incorrect

presentations of the security code. After four consecutive incorrect security code presentations, the

first four bits of the SCAC will all be written to “0”, and the user is permanently blocked from access to

the application zones, as well as to other areas controlled by the security code. After a successful

presentation of the security code, the entire 16-bit SCAC, including the four active bits, should be

erased. This verifies that the correct security code has been presented, since an erase operation in

this area is not allowed without SC verification. It also clears the SCAC bits in preparation for the next

use of the card. This erase operation will also clear the remaining 12 bits of the 16-bit SCAC word.

These 12 bits may be used in an application, although the entire 16-bit word will be erased if any bit in

the SCAC is erased.

Code Protected Zone

CPZ (64 bits)

Read access to this area is always allowed and does not require SC validation. The security code

must be correctly presented to allow write access to the code-protected zone.

Application Zone 1

AZ1 (256 bits)

AZ1 is intended to hold user application data. P1 (address 176) controls write access and R1

(address 177) controls read access within Zone 1. In Security Level 1, erasing AZ1 is accomplished

by performing an erase operation on any bit within AZ1, after verification of the security code (SV flag

= 1). This operation will erase the entire zone. In Security Level 2, erase operations are controlled by

both the SV flag and the erase key EZ1. See the erase definition in

Table 14-1 on page 16 for

specific details. There is no limit to the number of erase operations performed in AZ1. In Security

Level 1, write operations in AZ1 may be performed on single bits after verification of the security code.

In Security Level 2, the P1 bit must also be set to “1” to allow single bit write operations. Read

operations in Security Levels 1 and 2 are allowed if either R1 is set to “1” or the SV flag is set to “1” by

validating the security code.

Application Zone 1 Erase

Key EZ1 (48 bits)

The erase keys are passwords used to control erase operations within the application zones, after the

issuer fuse has been blown (Security Level 2). The erase key password is written during

personalization (Security Level 1), after verification of the security code. EZ1 can not be changed

after the issuer fuse is blown. In Security Level 2, AZ1 can be erased only after both the security code

and the EZ1 password have been validated. Verification of EZ1 will set the internal flag E1 to “1”.