Rainbow Electronics MAX66120 - Manual (Page 19)

MAX66120
ISO 15693-Compliant 1Kb Memory Fob
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Write AFI
The Write AFI command writes the AFI byte and
reports the success of the operation in the response.
The AFI byte can alternatively be defined by writing to
the proper location in memory block 10h using the
Write Single Block command.
Lock AFI
The Lock AFI command permanently locks (write pro-
tects) the AFI byte and reports the success of the oper-
ation in the response. Before using the Lock AFI
command, the AFI byte should be written to the device
using the Write AFI command. The AFI byte can alterna-
tively be locked by writing the AFI lock byte in memory
block 11h to AAh, using the Write Single Block com-
mand.
Write DSFID
The Write DSFID command writes the DSFID byte and
reports the success of the operation in the response.
The DSFID byte can alternatively be defined by writing
to the proper location in memory block 10h using the
Write Single Block command.
Lock DSFID
The Lock DSFID command permanently locks (write
protects) the DSFID byte and reports the success of the
operation in the response. Before using the Lock DSFID
command, the DSFID byte should be written to the
device using the Write DSFID command. The DSFID
byte can alternatively be locked by writing the DSFID
lock byte in memory block 11h to AAh, using the Write
Single Block command.
CRC Generation
The ISO 15693 standard uses a 16-bit CRC, generat-
ed according to the CRC-16-CCITT polynomial func-
tion: X
16 + X 12 + X 5 + 1 (see Figure 17). This CRC is
used for error detection in request and response data
packets and is always communicated in the inverted
form. After all data bytes are shifted into the CRC gen-
erator, the state of the 16 flip-flops is parallel-copied
to a shift register and shifted out for transmission with
the LSb first. For more details on this CRC, refer to
ISO/IEC 15693-3, Annex C.
REQUEST FLAGS COMMAND UID AFI VALUE
(1 Byte) 27h (8 Bytes) (1 Byte)
* If this command is processed without any error, the slave responds with a response flags byte of 00h.
REQUEST FLAGS COMMAND UID
(1 Byte) 28h (8 Bytes)
* If this command is processed without any error, the slave responds with a response flags byte of 00h.
REQUEST FLAGS COMMAND UID DSFID VALUE
(1 Byte) 29h (8 Bytes) (1 Byte)
* If this command is processed without any error, the slave responds with a response flags byte of 00h.
Request Data for the Write AFI Command*
Request Data for the Lock AFI Command
Request Data for the Write DSFID Command
Request Data for the Lock DSFID Command
REQUEST FLAGS COMMAND UID
(1 Byte) 2Ah (8 Bytes)
* If this command is processed without any error, the slave responds with a response flags byte of 00h.