SCL3711
R
EFERENCE
M
ANUAL
42
6.4.1.5. Write-No-Erase Byte (WRITE-NE)
Description
This command writes a byte value on an individual memory byte within the static memory
model area of blocks 0x0-0xE.
This command does not erase the value of the targeted byte before writing the new data.
Execution time of this command by NFC Forum tags type 1, is approximately half that of the
normal write command (WRITE-E). Using this command, EEPROM bits can be set but not
reset.
Format
CLA
INS
P1
P2
P3
Data
0xFF
0x58
0x00
Byte Address 0x01
1 byte of data to be written
Where P2 is coded as follow
Bit #
Value
Description
b0 – b2
Byte number to be addressed(value between 0x0 and 0x7)
b3 – b6
Block number (value between 0x0 and 0xE)
b7
(0)b
Number of the key to be used for authentication
Response
Data
SW1 SW2
Value of the memory byte after execution
0x90 0x00
Example
Sending the following command to an NFC Forum type 1 tag that has the value 0x39 in the first
EEPROM byte of block 0x1 of its static memory model area
CLA
INS
P1
P2
P3
Data
0xFF
0x58
0x00
0x10
0x01
0xA8
Will give the answer
Data
SW1 SW2
0xB9
0x90 0x00
0x39=(00111001)b
0xA8=(10101000)b
0xB9=(10111001)b