ATA559001-DDT Atmel, ATA559001-DDT Datasheet - Page 19

• Manufacturer Part Number: ATA559001-DDT
• Description: RF Wireless Misc UHF (1kbit r/w anti-collision)
• Manufacturer: Atmel

4.2.2
4.3
4817C–RFID–03/07
Frame Concept
Status2 Register
Register status2 gives an overview of the status of communication. It is part of a backscattered
message during program commands and read commands.
Table 4-3.
Communication is based on the following frames:
These three frames are elementary parts of the forward and return links.
Figure 4-1.
During the header it is possible to work in full duplex mode to optimize the link. Under control of
the reader, the return link can operate in a loop until the reader sends an EOT frame.
The return link is arranged as a synchronous link. The reader transmits the boundaries of the bit
by sending notches to achieve higher SNR. The maximum time for this bit as well as the spec-
trum of the backscattered bit shall be adjusted by the reader by tuning the return link header.
• A header frame for timing adjustments
• A data frame to transport the data (Forward: reader to tag, and Return: tag to reader)
• In the return link, the data frame contains the required data, if possible, and, as a function of
• An end of transmission (EOT) frame to mark the end of the forward or return link.
the command, the status2 information. A CRC is also part of the data frame.
Index
– In the forward direction, the data frame contains the command, the parameters, the
7
6
5
4
3
2
1
0
CRC value, and, if necessary, the address vectors and the data for programming.
The length of the data frame depends on the command and the selected addressing
mechanism.
Tag to reader
Reader to tag
Contents of Status2 Register
Frame Ordering During the Default Communication
Read Commands
Pre_select
ID
Lock protected
1
Bit length not ok
Aloha
CRC wrong
0
Header
Listen
Data
EOT
Program Commands
Pre_select
ID
Lock protected
1
Program_ok
Aloha
CRC wrong
0
Full duplex
Header
Loop
Data
Listen
EOT
ATA5590
19