Omron V740 Series, Руководство по эксплуатации

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V740 RFID READER ANTENNA NOTE. SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE. REV. 1.1
OPERATION MANUAL
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© OMRON CORPORATION 2004
RQL Table Schema
As was mentioned before, RQL is derived from the SQL language, which allows the user to define arbitrary
tables. RQL has predefined tables according to the schema below. NOTE: Tag_id and Tad_data values are
case-sensitive and are all lowercase only.
Read/Write Tag_id Type Read/Write Tag_data Type
R protocol Int R id Hex String
R antenna Int R/W blocknum Int
R/W id Hex String R/W data Hex String
W killed Int R locked Int
W password Hex String
R/W locked Int
R frequency Int
R dspmicros Int
R timestamp string
Read/Write Tag_id Type
R version String
R supported_p
rotocols
String
Read/Write Settings Type
R current_time String
Detailed Command Structure
Select, Where, Set
The SELECT command is for querying the tag population
of the Reader as well as static variables such as firmware
version and supported protocols. The structure of a
SELECT command is as follows:
SELECT select_list FROM
table_expression
[where_specification]
[set_specification];
A
where_specification
is entered as:
WHERE boolean_expr
boolean_expr
can consist of any expression which
evaluates to a boolean value. In many cases, this
expression will be:
expr binary_operator expr
or
unary_operator expr
where
binary_operator
can be one of =, <, <=, >,
>= , <>, AND, or OR, and
unary_operator
can
be “NOT”. Parentheses may also be used to create
associations of subexpressions. In the presence of a
WHERE clause, SELECT will not return any rows for
which the WHERE condition does not evaluate to
TRUE.
A
set_specification
is entered as:
SET expression
In the following we provide some more examples for
the usage of
SELECT, WHERE, SET
:
•
To query a specific tag, given its ePC code, one
can specify a specific tag with id as a hexadecimal
number
:
SELECT id FROM tag_id WHERE id=id AND
antenna_id=antenna_id;
SELECT id FROM tag_id WHERE id=id SET
time_out=500;
The Reader returns the tag if the tag is present
followed by an empty event (‘\n’) or an empty