ATA559001-6DSY Atmel, ATA559001-6DSY Datasheet - Page 52

• Manufacturer Part Number: ATA559001-6DSY
• Description: RF Wireless Misc UHF (1k bit r/w anti-collision)
• Manufacturer: Atmel

Specifications of ATA559001-6DSY

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

8. Forward Stream
8.1
52
Forward Header
ATA5590
The forward header consists of 4 symbols. The time between the notches is measured by
ATA5590. Some of these timings are the base for PIE of the forward link. The timing relations
are also checked by ATA5590. This mechanism is used to find the header, which results in a
first pre-synchronization.
The tag itself measures the time between two notches, which means that this measurement is
independent from the length of the notch signal.
Figure 8-1.
Note:
Figure 8-1
The header is accepted by the tag if the check1 and the EOF* symbols are longer than the 0*
symbol. If the header is not accepted, ATA5590 continues to search for a valid header as long
as it receives symbols from a reader.
• The link is based on a relative timing, considering the length of the symbols transmitted
• The boundaries between the symbols are marked by notch signals. The notch signal is
during the header.
generated by the reader by changing the polarity of the modulation (PR-ASK) or by a
traditional AM signal.
The EOT symbol at the end of a command or at the end of the synchronous return link is a combi-
nation of two EOF symbols.
The forward header
shows
clock_ctrl
Principal Timing (the Pulses are Generated by Notches)
0*
check1
timing of 0*
timing of EOF*
symbol interpreted as a binary 0
symbol interpreted as a binary 1
symbol interpreted as an EOF symbol
time
EOF*
symbols used inside the
header sub-symbols
data stream
4817C–RFID–03/07