SR176_07 Datasheet, PDF (14/35 Pages) STMicroelectronics – 13.56 MHz, 176-bit short range contactless user EEPROM with 64-bit Unique ID

Device operations (instructions)
5
Device operations (instructions)
SR176
All instructions, data and the CRC are transmitted to the SR176 in 10-bit character format
using ASK modulation. The start bit (b₀ of the 10 bits) is sent first. The command frame
received by the SR176 on the antenna is demodulated by the 10% ASK demodulator, and is
decoded by internal logic. Prior to any operation, the SR176 must have been previously
activated by an INITIATE command (as shown in Figure 13). Each frame transmitted to the
SR176 must start with a Start Of Frame, followed by one or more data characters, and is
ended by two CRC bytes and the End Of Frame. When an invalid frame is decoded by the
SR176 (because of a wrong instruction or CRC error), the memory does not send any error
code.
When a valid frame is received, the SR176 may have to send back data to the reader. For
this, it sends 10-bit characters back, with SOF, CRC and EOF, using the BPSK coding. The
transfer is ended by the SR176 sending the EOF.
Figure 13. State transition diagram
POWER-OFF
Out of
Field
In Field
READY
INITIATE()
ACTIVE
Out of
Field
Out of
Field
SELECT(Chip_ID)
DESELECTED
SELECT( =/ Chip_ID)
SELECT(Chip_ID)
SELECTED
COMPLETION
Out of
Field
DEACTIVATED
SELECT(Chip_ID)
READ_BLOCK()
WRITE_BLOCK()
PROTECT_BLOCK()
GET_PROTECTION()
AI09063B
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