6

AT88SC153

1016D–SMEM–04/04

Configuration Zone

Answer-to-reset

32-bit register defined by Atmel

Lot History Code

32-bit register defined by Atmel

Fab Code

16-bit register defined by Atmel

Card Manufacturer Code

16-bit register defined by the card manufacturer

Issuer Code

64-bit register defined by the card issuer

Access Registers

Three 8-bit access registers defined by the issuer, one for each user zone (active low)

Table 6. Access Registers

Write Password Enable (WPE): If enabled (WPE = “0”), the user is required to verify

the write password to allow write operations in the user zone. If disabled (WPE = “1”), all

write operations are allowed within the zone. Verification of the write password also

allows the read and write passwords to be changed.

Read Password Enable (RPE): If enabled (RPE = “0”), the user is required to verify

either the read password or write password to allow read operations in the user zone.

Read operations initiated without a verified password will return $00 (or the status of the

fuse bits, if either CMA or PER are still intact). Verification of the write password will

always allow read access to the zone. RPE = “0” and WPE = “1” is allowed but is not

recommended.

Authentication Enable (ATE): If enabled (ATE = “0”), a valid authentication sequence

is required for both read and write and must be completed before access is allowed to

the user zone. If disabled (ATE = “1”), authentication is not required for access.

Authentication Only for Write (AOW): If enabled (AOW = “0”), a valid authentication

sequence must be completed before write access is allowed to the user zone. Read

access to this zone is allowed without authentication. This bit is ignored if ATE is

enabled.

Password Select (PWS): This bit defines which of the two password sets must be pre-

sented to allow access to the user zone. Each access register may point to a unique

password set, or access registers for multiple zones may point to the same password

set. In this case, verification of a single password will open several zones, combining the

zones into a single larger zone.

Write Lock Mode (WLM): If enabled (WLM = “0”), the 8 bits of the first byte of each user

zone page will define the locked/unlocked status for each byte in the page. Write access

is forbidden to a byte if its associated bit in byte 0 is set to “0”. Bit 7 controls byte 7, bit 6

controls byte 6, etc.

Modify Forbidden (MDF): If enabled (MDF = “0”), no write access is allowed in the

zone at any time. The user zone must be written before the PER is blown.

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

WPE

RPE

ATE

AOW

PWS

WLM

MDF

PGO