User's Manual

HF Mifare Easy Module V1.0
ACG Identification Technologies GmbH 59
8.5 Mifare
®
Standard Sector Trailer and Access Conditions
The last block of each sector contains configuration data for the sector. This
configuration data includes key A, key B and the access conditions. The first six byte
(byte 0…5) of the Sector Trailer contain key A data, the last six bytes (byte 10…15)
contain key B data.
Byte number 6 to byte number 9 contain the access conditions for each block of the
sector. It is possible to configure the access rights (read, write, increment,
decrement, restore) different for each block in the sector and in dependence to the
key used in the authentication (login) procedure.
Access conditions for the Sector Trailer himself are different form access conditions
of a data block (increment, decrement, copy is never allowed for the Sector Trailer as
of course this block never contains value data). The access conditions are stored
redundant for data security reasons.
Please consider that enabled keys are not readable and therefore return 00 on
reading.
It is possible to configure each block of one sector as Value Block (Ticketing) or Data
Block.
As an example you may use the following values for the access rights:
Block 0 Block 1 Block 2 Sector Trailer
V V V 08 77 8F FF
V V D 48 77 8B FF
V D V 28 77 8D FF
V D D 68 77 89 FF
D V V 18 77 8E FF
D V D 58 77 8A FF
D D V 38 77 8C FF
D D D 78 77 88 FF
Where “D” denotes a data block and “V” value block. All access conditions are
configured that way that key B has write access to the Sector Trailer and so may
change the configuration.
Each of the 16 sectors consists of 4 blocks (including the sector trailer). Block 0 of
sector 0 contains the serial number and some manufacturer data. It is read only.
For detailed description of the Sector Trailer /Access Conditions please refer to the
datasheets of your chip manufacturer. As it is possible to destroy the tag
(permanently make a block read and write protected) it is strongly recommended not
to change the Sector Trailer without detailed knowledge and under safe environment
with good reading/writing only.