SR176_07 Datasheet, PDF (20/35 Pages) STMicroelectronics – 13.56 MHz, 176-bit short range contactless user EEPROM with 64-bit Unique ID

Device operations (instructions)
SR176
5.6
WRITE_BLOCK
Command Code = 09h,(X.AD)
Prior to any WRITE_BLOCK command, the SR176 must have been set into the SELECTED
state.
When executing the WRITE_BLOCK command, the SR176 overwrites the contents of the
addressed block with the 16-bit value that was sent in the command, provided that the block
is available and not write protected. The AD value of the four least significant bits of the
address code (X.AD) (b₃ to b₀) represents the block address. For example, address 06h
specifies that the data should be written in block 6. The SR176 does not generate any
response when it executes a WRITE_BLOCK command (Figure 30). The reader must check
after the programming time, t_W, that the data bits were correctly programmed.
Block addresses between 0 to 3 cannot be accessed using the WRITE_BLOCK command
(the command has no effect on these blocks). Write access to block 15 is described in the
section on the PROTECT_BLOCK command.
Request parameters (Figure 29):
● ADDRESS: address block from 4 to 14
● DATA_L: least significant Byte
● DATA_H: most significant Byte
Figure 29. WRITE_BLOCK request format
SOF WRITE_BLOCK ADDRESS DATAL
DATAH
CRCL
CRCH EOF
09h
4 zero-bits
8 bIts
8 bIts
+ 4-bit address
8 bIts
8 bIts
AI07709B
Figure 30. WRITE_BLOCK frame exchange between Reader and SR176
Reader
SR176
SOF 09h ADDR DATAL DATAH CRCL CRCH EOF
No Response
AI07710B
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