xra00 STMicroelectronics, xra00 Datasheet - Page 24

• Manufacturer Part Number: xra00
• Description: Uhf, Epcglobal Class 1b, Contactless Memory Chip 96 Bit Epc With Inventory And Kill Function
• Manufacturer: STMicroelectronics

XRA00
BASIC COMMANDS - OVERVIEW
The XRA00 provides six Basic commands, de-
scribed in the following paragraphs.
ScrollID
The ScrollID command is a Basic command that
gives rise to a response from the XRA00.
When the ScrollID command is issued, the XRA00
responds if the data sent by the Reader in the
[VALUE] field matches the XRA00's internal mem-
ory starting at the location specified by the [PTR]
field. Data in the [VALUE] field is compared to the
XRA00 memory, from the lowest to the highest ad-
dress. Only XRA00 devices that match all of the
bits in the [VALUE] field reply to the Reader.
XRA00 devices that fail the match or fail a parity
test on any of the parity bits do not modulate.
The XRA00 devices that match the data sent by
the Reader reply by sending back an 8-bit pream-
ble, a 16-bit CRC for error checking followed by
the entire 96-bit ePC code.
Data sent by the Reader to the XRA00 may be of
variable length. ScrollID can be used to look for
Table 8. Example of a ScrollID Operation
24/40
XRA00 1 ID
XRA00 2 ID
XRA00 3 ID
Bit Number
Any unlocked XRA00 seeing the command
will reply by sending back an 8-bit preamble,
16-bit CRC and its entire 96-bit ePC code,
plus the Kill code and Lock code location bits.
Any locked XRA00 seeing the command will
reply by sending back an 8-bit preamble, 16-
bit CRC and its entire 96-bit ePC code.
Towards Highest
Address Bit
...010001000001011011101010
...100111100001001010010010
...101101010001011011110111
...321098765432109876543210
XRA00 ID Code/Bit Number
Lowest Address Bit
b
b
b
specific XRA00 devices or test for the presence of
specific groups of XRA00 devices in the field. Data
sent by the XRA00 has a fixed length.
Example of a ScrollID Command . A Reader is-
sues a command containing the following data:
[CMD] =
[PTR] =
[LEN] =
[VALUE] = 000101101
XRA00 devices will attempt to check 9 bits of their
address data, starting at bit 7, against the data
specified in the [VALUE] field. XRA00 devices
whose data matches respond with a ScrollID Re-
ply.
Table 8.
XRA00 1 and XRA00 3 respond to the command
but XRA00 2 does not. Underlined bits in XRA00
memory are compared with the [VALUE] data.
Here, bits 7 through 15 are compared.
The XRA00 devices start by modulating the lowest
memory address data bit onward up to the highest
memory address data bit. This means that in
8., modulation is from right to left.
shows the case of three XRA00 devices.
XRA00 responds to ScrollID command
00000001
00000111
00001001
NO (bit 10 fails to match)
b
b
b
b
YES
YES
(ScrollID)
(0x07)
(0x09)
(0x2D)
-
Table