INfinity 510 Protocol Reference Guide - Sirit

Chapter 6 - Tag Protocol Support
As described previously, return_link_freq, tari, and
data_1_length are all read-only. In order to configure these variables,
the modem.protocol.isoc.physical.set() function is used to set
all three variables simultaneously:
modem.protocol.isoc.physical.set(tari=tari_12_50,
return_link_freq=lf160, data_1_length=d1_len_20)
FILTERING
The reader can send additional ISO-C Select commands to filter the tag
population prior to an inventory round. To enable filtering in the reader, the
modem.protocol.isoc.filtering.enabled variable must be set
to true.
Once set, select commands are sent if any filters are enabled, regardless of
the modem.protocol.isoc.control.select_cmd_enable
variable’s setting. The memory bank used for filtering is set using the
modem.protocol.isoc.control.mem_bank_for_selection
variable.
Each filter uses a modem.protocol.isoc.filter.X namespace,
where X is 1 to 8 for the 8 filters. The following variables exist in each
namespace:
Enabled
Action
Length
Offset
Mask
If true, this filter is enabled.
What action to take with this filter. Choices include:
ASSERT_DEASSERT, ASSERT_NOTHING,
NOTHING_DEASSERT, NEGATE_NOTHING,
DEASSERT_ASSERT, DEASSERT_NOTHING,
NOTHING_ASSERT, NOTHING_NEGATE.
Each choice corresponds to a Select Action described in the ISO-
C specification. The first part of each choice describes actions
taken with tags that match the filter (Assert inventoried or SL,
deassert it, negate it, or do nothing). The second part describes
actions taken with tags that do not match.
Length, in bits, of this filter.
Bit location where the mask comparison will begin.
This mask is compared against the tag’s memory to determine if
the tag matches. The first bit of this mask is compared to the
offset bit of the tag’s memory, and the mask should be
length bits long.
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