ATA555811C-DDB Atmel, ATA555811C-DDB Datasheet - Page 27

• Manufacturer Part Number: ATA555811C-DDB
• Description: IC IDIC 1KBIT R/W DIE
• Manufacturer: Atmel

Specifications of ATA555811C-DDB

• Function: Read/Write
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

7.2
7.3
4681E–RFID–11/09
Read Single Block
Read Multiple Blocks
A Read Single Block command is executed on a tag in the Selected state. It serially reads a
complete 32-bit tag data block. A downlink CRC (CRC_d) can be optionally included. This acts
as a check for the block address. If included, the tag will always check the CRC_d and abort the
command if it not compatible with the received address. If omitted, the tag will perform no down-
link CRC check.
The tag responds to a single block read command with the requested 32-bit data block which is
always followed by a 16-bit uplink CRC (CRC_u) to ensure data and address integrity. A read
protected or non-existent memory block will return a block of 1 data bits (FFFF FFFF). A suc-
cessful execution of a LoginRead command is necessary before reading a protected memory
block.
It should be noted that the 16-bit CRC_u is generated from both the block address parameter
and retrieved data. So that it acts as a check for the complete command transaction. From the
received CRC_u, the interrogator can ensure that the data is correct and that it was read from
the correct requested block address.
Table 7-3.
Table 7-4.
Note:
A Read Multiple Blocks command is executed on a tag in the Selected state. It serially reads an
array of consecutive 32-bit tag data blocks from a start address through to and including an end
address. A downlink CRC (CRC_d) can be optionally included. This acts as a check for both
block address parameters. If included the tag will always check the CRC_d and abort the com-
mand if it is not compatible with the received addresses. If omitted, the tag will perform no
downlink CRC check.
The tag responds to a read command with the requested 32-bit data blocks which are always
followed by a single 16-bit uplink CRC (CRC_u) to ensure data and address integrity. A read
protected or non-existent memory block will return a block of 1 data bits (FFFF FFFF). A suc-
cessful execution of a LoginRead command is necessary before reading a memory array
including protected memory blocks.
It should be noted that the 16 bit CRC_u is generated from both the address parameters and
retrieved data so that it acts as a check for the complete command transaction. From the
received CRC_u, the interrogator can ensure that the data is correct and that it was read from
the correct requested block address range.
Command
Read Single Block = 00 01
4 bits
SOF
Start of Frame
3 .. 10-bit periods
1. optional
Interrogator Command Parameters
Tag Response
Data
Data Block
32 bits (MSB first)
Parameter 1
Block Address
6 bits (MSB first)
CRC
CRC_u (Block Addr + [CRC_d
16 bits (MSB first)
CRC (optional)
CRC_d (Block Addr)
16 bits (MSB first)
(1)
] +Data)
ATA5558
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