Data Sheet

001052 © NXP B.V. 2007. All rights reserved.
Product data sheet Rev. 5.2 — 15 January 2007 9 of 17
NXP Semiconductors
MF1 IC S50
Functional specification
• Adr: Signifies a 1-byte address, which can be used to save the storage address of a
block, when implementing a powerful backup management. The address byte is
stored four times, twice inverted and non-inverted. During increment, decrement,
restore and transfer operations the address remains unchanged. It can only be
altered via a write command.
6.6.3 Sector trailer (block 3)
Each sector has a sector trailer containing the
• secret keys A and B (optional), which return logical “0”s when read and
• the access conditions for the four blocks of that sector, which are stored in bytes 6...9.
The access bits also specify the type (read/write or value) of the data blocks.
If key B is not needed, the last 6 bytes of block 3 can be used as data bytes.
Byte 9 of the sector trailer is available for user data. For this byte apply the same access
rights as for byte 6, 7 and 8.
Fig 6. Value blocks
Byte Number
1514131211109876543210
Description
AdrValue Value Value Adr Adr Adr
Fig 7. Sector trailer
Byte Number
1514131211109876543210
Description
Key A Access Bits Key B (optional)