T555711-DDW Atmel, T555711-DDW Datasheet - Page 10

• Manufacturer Part Number: T555711-DDW
• Description: IC IDIC R/W RFID 330BIT ON-CHIP
• Manufacturer: Atmel
• Series: T555711r

Specifications of T555711-DDW

• Rf Type: Read / Write
• Frequency: 125kHz
• Features: 330-bit EEPROM
• Package / Case: DICE
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Figure 4-5.
Figure 4-6.
4.9
10
T55571x
POR
Password
Standard write
Protected write
Direct access (PWD = 1)
Direct access (PWD = 0)
Page 0/1 regular read
AOR (wake-up command)
Reset command
T5557
Block 0 loading
T555701
Complete Writing Sequence
T5557 Command Formats
Read mode
When password mode is active (PWD = 1), the first 32 bits after the opcode are regarded as the
password. They are compared bit by bit with the contents of block 7, starting at bit 1. If the com-
parison fails, the T5557 will not program the memory, instead it will restart in regular-read mode
once the command transmission is finished.
Note:
Each transmission of the direct access command (two opcode bits, 32 bits password, “0” bit plus
3 address bits = 38 bits) needs about 18 ms. Testing all possible combinations (about 4.3 billion)
takes about two years.
Start gap
In password mode, MAXBLK should be set to a value below 7 to prevent the password from being
transmitted by the T5557.
1p*
1p* L
1p*
1p*
1p*
OP
10
00
Opcode
1
1
1
0
1
2 Addr
Password
Password
Password
0
Lock bit
Data
Block data
32
32
32
Write mode
32
* p = page selector
L
0
2 Addr
1
2 Addr
address
Block
0
0
Data
Programming
32
2 Addr
Read mode
4517J–RFID–03/06
0