User's Manual

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READER=>HOST: 0x00 – ACK byte
0x6D – related command code MFDF_WRITE_DATA
3.5.15 Read data (0x6E)
This command reads data from standard data files or backup data files. It takes three arguments: the file
number, the offset in the file where data is stored, and the number of bytes to be read. The returned ACK
response contains the data that has been read.
Command description
Argument
Size
Value
Description
Command ID
1
0x6E
MFDF_READ_DATA
File number
1
X
File number inside application
File offset
3
X
file offset, 3
-
bytes LSB value
Data length
3
X
Read data length, 3
-
bytes LSB value
Response description
ACK
1
0x00
Command ID
1
0x6E
MFDF_READ_DATA
Example:
HOST=>READER: 0x6E – MFDF_READ_DATA
0x01 – file number
0x00 0x00 0x00 – zero offset
0x07 0x00 0x00 – seven bytes to read
READER=>HOST: 0x00 – ACK byte
0x6E – related command code MFDF_READ_DATA
0x01 0x02 0x03 0x04 0x05 0x06 0x07 - data
3.5.16 Create value file (0x6F)
This command creates files for the storage and manipulation of 32bit signed integer values within an
existing application on the TAG. It takes seven arguments listed in the table below.
Command description
Argument
Size
Value
Description
Command ID
1
0x6F
MFDF_CREATE_VALUE_FILE
File number
1
X
File number inside application
Access rights
2
X
Please refer to the NXP documentation for more information
Low limit
4
X
Low limit as 4
-
bytes signed value, LSB first
Up limit
4
X
Up limit as 4
-
bytes signed
value, LSB first
Initial value
4
X
Initial value as 4
-
bytes signed value, LSB first
Get free enabled
1
X
Please refer to the NXP documentation for more information