The macros ?¬?le has a declarations section and a main section. The declarations
section allows the user to predeclare the lengths of all of the corresponding ?¬?elds that occur
in each of the primitives and responses. In the section identi?¬?ed as main, the primitives
and their speci?¬?c responses are de?¬?ned in terms of their ?¬?elds.
The speci?¬?c ?¬?elds can be easily described, as illustrated in Figure 3.22. This provides the
user with the ability to adopt any level of granularity to manipulate the primitives and
their corresponding responses. For example, in the macros illustrated in the ?¬?gure, the
string denoting the Write command is write. The decimal value of the command code for
this speci?¬?c command is 195, stored using 8 bit.
Interrogator issues Req_RN
containing same RN16
Interrogator Tag
Interrogator accesses tag.
Each access command uses
handle as a parameter
Tag verifies handle. Tag ignores
command if handle does not match
5
6
7
8
Interrogator acknowledges
Tag by issuing Ack with
same RN16
3
Two possible outcomes:
1. Valid RN16: Tag responds with {PC, EPC}
2. Invalid RN16: No reply
4
Interrogator issues a Query,
QueryAdjust, or QueryRep 1
Two possible outcomes:
1. Slot = 0: Tag responds with RN16
2. Slot <> 0: No reply
2
Query/Adjust /Rep
Ack (RN16)
RN16
{PC, EPC}
Req_RN (RN16)
Handle
Command ( handle )
Notes:
??“ CRC-16 not shown in transitions
??“ See command /reply tables for command details
Two possible outcomes:
1.
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