SRI4K-SBN181GE STMICROELECTRONICS [STMicroelectronics], SRI4K-SBN181GE Datasheet - Page 15

• Manufacturer Part Number: SRI4K-SBN181GE
• Description: 13.56 MHz short-range contactless memory chip with 4096-bit EEPROM and anticollision functions
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

SRI4K
4.1
Resettable OTP area
In this area contains five individual 32-bit Boolean words (see
area). A Write_block command will not erase the previous contents of the block as the write
cycle is not preceded by an auto-erase cycle. This feature can be used to reset selected bits
from 1 to 0. All bits previously at 0 remain unchanged. When the 32 bits of a block are all at
0, the block is empty, and cannot be updated any more. See
examples of the result of the Write_block command in the resettable OTP area.
Figure 12. Resettable OTP area (addresses 0 to 4)
Figure 13. Write_block update in Standard mode (binary format)
The five 32-bit blocks making up the resettable OTP area can be erased in one go by adding
an auto-erase cycle to the Write_block command. An auto-erase cycle is added each time
the SRI4K detects a Reload command. The Reload command is implemented through a
specific update of the 32-bit binary counter located at block address 6 (see
bit binary
Figure 14. Write_block update in Reload mode (binary format)
Previous data stored in block
Data to be written
New data stored in block
Previous data stored in block
Data to be written
New data stored in block
Block
address
0
1
2
3
4
counters” for details).
MSb
b31
b31
b31
b24 b23
1
1
1
1
1
1
...
...
...
...
...
...
1
1
1
1
1
1
32-bit Boolean area
32-bit Boolean area
32-bit Boolean area
32-bit Boolean area
32-bit Boolean area
1
0
0
32-bit block
1
1
1
b16 b15
0
0
0
0
1
1
1
1
1
1
1
1
0
0
0
0
0
0
1
1
1
1
1
1
b8 b7
Figure 13
1
1
1
1
1
1
Figure 12
1
0
0
1
0
0
LSb
b0
1
0
0
1
0
0
and
for a map of the
Memory mapping
1
1
1
1
1
1
“Section 4.2: 32-
Figure 14
Resettable
OTP bit
Description
0
1
0
0
1
1
1
1
1
1
1
1
ai07657b
ai07658
for
ai07659
15/45
1
1
1
1
1
1
b0
b0