SR176_07 Datasheet, PDF (16/35 Pages) STMicroelectronics – 13.56 MHz, 176-bit short range contactless user EEPROM with 64-bit Unique ID

Device operations (instructions)
SR176
5.2
SELECT(Chip_ID)
Command Code = 0Eh,(X.ID)h
Prior to any memory access, the SR176 must have been set in the SELECTED state by a
SELECT() command. All other commands sent to the SR176 before the SELECT(), except
INITIATE(), are ignored. In response to receiving the SELECT() command, the SR176
sends back its Chip_ID, using an 8-bit format (Figure 21).
Any SR176 that is already in the SELECTED state, and which receives a SELECT()
command that does not match its Chip_ID, is automatically put in the DESELECTED state.
The SR176 stays in the SELECTED state up to the reception of a COMPLETION or a
SELECT with a non-matching Chip_ID.
After a PROTECT_BLOCK command, it is necessary to send a new SELECT command in
order to load enable the write access again in the internal logic. If a SELECT is not send, the
SR176 keeps the previous write access rights.
Request parameters (Figure 18):
● Chip_ID (formatted as shown in Figure 20)
Response parameters (Figure 19):
● Chip_ID (formatted as shown in Figure 20)
Figure 18. SELECT request format
SOF
SELECT
0Eh
Chip_ID
4 reserved bits
+ 4-bit ID
CRCL
8 bits
Figure 19. SELECT response format
CRCH
8 bits
EOF
AI07702B
SOF
Chip_ID
4 reserved bit
+ 4-bit ID
CRCL
8 bits
CRCH
8 bits
EOF
AI07703B
Figure 20. 8-bit Chip_ID format
b7
b6
b5
b4
b3
b2
b1
b0
Test bits (block 15)
b3
Block 15
4-bit Chip_ID of the SR176
b0
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