M24LR04E-RDW6T/2 STMicroelectronics, M24LR04E-RDW6T/2 Datasheet - Page 72

• Manufacturer Part Number: M24LR04E-RDW6T/2
• Description: EEPROM 4-Kbit Dual EEPROM 1.8 to 5.5V 13.56Mhz
• Manufacturer: STMicroelectronics

Specifications of M24LR04E-RDW6T/2

• Product Category: EEPROM
• Memory Size: 4 Kbit
• Maximum Clock Frequency: 400 KHz
• Maximum Operating Current: 20 uA
• Operating Supply Voltage: 1.8 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: TSSOP-8
• Factory Pack Quantity: 1

Anticollision
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Anticollision
The purpose of the anticollision sequence is to inventory the M24LR04E-Rs present in the
VCD field using their unique ID (UID).
The VCD is the master of communications with one or several M24LR04E-Rs. It initiates
M24LR04E-R communication by issuing the Inventory request.
The M24LR04E-R sends its response in the determined slot or does not respond.
Request parameters
When issuing the Inventory Command, the VCD:
Table 33.
In the example provided in
added to the mask value MSB. The 11-bit mask and the current slot number are compared
to the UID.
Table 34.
MSB
SOF
sets the Nb_slots_flag as desired,
adds the mask length and the mask value after the command field.
The mask length is the number of significant bits of the mask value.
The mask value is contained in an integer number of bytes. The mask length indicates
the number of significant bits. LSB is transmitted first.
If the mask length is not a multiple of 8 (bits), as many 0-bits as required are added to
the mask value MSB so that the mask value is contained in an integer number of bytes.
The next field starts at the next byte boundary.
Request_
0-bits added
(b
8 bits
flags
0000 0
15
Inventory request format
Example of the addition of 0-bits to an 11-bit mask value
) MSB
Command
8 bits
Table 34
Doc ID 022208 Rev 5
Optional
8 bits
AFI
and
Figure
length
Mask
8 bits
50, the mask length is 11 bits. Five 0-bits are
11-bit mask value
100 1100 1111
LSB (b
0 to 8 bytes
Mask value
0
)
16 bits
CRC
M24LR04E-R
EOF
LSB