EMS LRP2000 Series, Руководство оператора

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RFID Interface
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LRP820S-Series Long-Range Passive Reader/Writers
Multi-tag Command Parameters
Tag Repeat Count
This parameter is used on the multi-tag Continuous Read commands,
83H and 8DH. After Continuous Read is initiated, any tag that comes
within range of the antenna will be read and the requested data from
the tag will be sent to the host. The Tag Repeat Count parameter
represents the number of other tags which must be read before the
data from the first tag will be sent for a second time. This count is
implemented to enable the operator to limit the volume of information
sent by the controller. In this way, it is functionally similar to the Delay
parameter used in the single-tag Continuous Read command. The
difference between the two is that the single-tag parameter indicates
an amount of time for which a tag must remain out of range of the
antenna in order for its data to be sent a second time. The Tag Repeat
Count is strictly the number of tags whose data will be sent before the
data from a certain tag is sent again. With this Count parameter set to
00H, the controller will repeatedly send the requested information until
the tags are out of range.
Selectively Reading and Writing Tags By Family
The multi-tag commands always have a Family Code as a parameter.
This parameter manages the reads and writes when multiple tags are
in the reading field. This parameter can be used to differentiate
between tags without communicating directly with all of the tags in the
field at one time. In this condition it is still possible to communicate
with individual tags through the use of commands 94H, 95H, and 96H.
These commands operate on one specific tag by including the tag's
unique serial number as a parameter. The Family Code is a one-byte
field in the tag which resides outside the read/write memory address
space. When the Family Code parameter is set to 0, the command is
broadcast to all the tags in the field. On the other hand, if the Family
Code parameter is set to a non-zero byte value, only tags with
implementing a multi-level organization of the tags, by permitting
thethe specified Family code will respond. This feature can help in
selective reading of tags by Family Code. This gives faster access to
the tags than by using Family Code zero. The Family Code byte can
be read, written, and locked independently of the rest of the read/write
address space in the tag.
Anticollision Index