Rev. 1.00
182
September 11, 2018
Rev. 1.00
183
September 11, 2018
HT45F4050
A/D NFC Flash MCU
HT45F4050
A/D NFC Flash MCU
UID collided conditions and the Data field will be determined bit-by-bit after the anticollision
identification. Eventually the 3-byte UID for the cascade level 1 will be identified.
After the 3-byte UID has been successfully identified, the NFC tag device can be selected by the
Select CL1 command for the cascade level 1. The response to the Select CL1 command is the
Select CL1 Acknowledge, SAK, with a value of 04h followed by the CRC bytes after the Select
CL1 command has fully executed. The Select CL1 command can still fully execute even if the CRC
value is incorrect. However, if the parity value is incorrect, the NFC tag device will directly return
to either the IDLE or HALT state according to its previous state without any response.
93
Command
Tag Device
Response
CMD.
88
UID0
CT
90
μ
s
20
PAR.
UID1 UID2 BCC0
Cascade Level 1 UID
Anticollision CL1 Execution Diagram
93
Command
Tag Device
Response
CMD.
04
CRC0
SAK
90
μ
s
70
PAR.
CRC1
88
UID0 UID1 UID2 BCC0
CT
Cascade Level 1 UID
CRC0 CRC1
Select CL1 Execution Diagram
Anticonllision CL2 – Anticollision Command for Cascade Level 2
Select CL2 – Select Command for Cascade Level 2
Command: Code
(CMD.)
Parameter
(PAR.)
Data
Integrity
mechanism
Response
Anticollision CL2: 95h
20h
—
Parity, BCC1
4 bytes CL2 UID
Anticollision CL2: 95h
21h to 67h
Part of CL2 UID
Parity, BCC1
Part of CL2 UID
Select CL2: 95h
70h
4 bytes selected UID Parity, BCC1, CRC
SAK (00h)
The Anticollision and Select commands for Cascade Level 2 are based on the same command
code. The main difference between these two commands is the
p
arameter byte. The parameter
byte is defined as 70h for the Select commands while this field is defined from 20h to 67h for the
Anticollision commands. The NFC tag device accepts these commands in the READY2 state only.
The response to the Anticollision CL2 command, "95h_20h", is the remaining 4 bytes of the 7
UID bytes in the cascade level 2 followed by the Block Check Character byte 1, BCC1. During the
anticollision process the parameter field value will be set to a certain value
ranging
from 21h to 67h
depending upon the UID collided conditions and the Data field will be determined bit-by-bit after
the anticollision identification. Eventually the remaining 4-byte UID for the cascade level 2 will be
identified.
After the remaining 4-byte UID has been successfully identified, the NFC tag device can be selected
by the Select CL2 command for the cascade level 2. The response to the Select CL2 command is
the Select CL2 Acknowledge, SAK, with a value of 00h followed by the CRC bytes after the Select
CL2 command has fully executed. The Select CL2 command can still fully execute even if the CRC
value is incorrect. However, if the parity value is incorrect, the NFC tag device will directly return
to either the IDLE or HALT state according to its previous state without any response.