ib technology

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Note that with each memory access the internal logic of the Mifare transponder verifies the

format of the access conditions. If it detects a format error then the entire sector is irreversibly

locked. Since the access bits themselves can be blocked for read/write operations, care must

be taken when cards are being personalised for a particular application or service provider.

Access Bits

Block Affected within a sector

(1k card and lower half of 4k card)

(Upper half of 4k card)

Block 0

(Data Block)

Blocks 0-4

(Data Blocks)

Block 1

(Data Block)

Blocks 5-9

(Data Blocks)

Block 2

(Data Block)

Blocks 10-14 (Data Blocks)

Block 3

(Sector Trailer)

Block 15

(Sector Trailer)

Note that the Access Conditions for individual blocks can be set on 1k cards and for lower

half of 4k card memory. However for the upper half of 4k cards the Access conditions are set

for groups of five blocks (except for Sector Trailer Block which is still individually set).

Access Conditions

The C1, C2, C3 access bits are stored in a specific non-inverted and inverted pattern in the

sector trailer of the particular sector. These bits control the Access Conditions for every data

block and sector trailer block.

Sector Trailer Block

Byte:

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

Bit 7

6

5

4

3

2

1

0

Byte 6

Byte 7

Byte 8

Byte 9

(

not used

)

Transport settings (factory defaults)

Byte 6

(1

1

1

1

1

1

1

1) = 0xFF

Byte 7

0

0

0

0

0

1

1

1) = 0x07

Byte 8

1

0

0

0

0

0

0

0) = 0x80

Byte 9

(

not used

)

KeyA (6 bytes)

Access Bits

KeyB (optional)