INfinity 510 Protocol Reference Guide - Sirit

Chapter 15 - Modem Namespace
modem.protocol.isoc.filtering.truncated_epc_response
This variable turns on ISO-C truncation. When truncation is true and filtering
is enabled, the mask filter is used and tags that match the mask will
truncate their EPC response to the bits that follow the mask. The mask
must end in the EPC memory or truncation will not be enabled.
For truncation to work, the filter mask must start at offset 16 in EPC
memory, which is the start of the Protocol-control (PC) bits. The most
significant 5 bits of the PC indicate the length of the tags EPC in 16-bit
words, plus the 1 word of PC bits. Only 1 filter mask can be used with
truncation.
The following example sets up a filter and uses truncation to find 96-bit EPC
tags with tag_id=301020304050xxxxxxxxxxxx, where x is don't care. The
length is 64 bits where: 64 bits = 16 (PC bits) + 48 bits (EPC bits in mask).
The offset is the offset to PC bits in EPC memory). The filter mask is
3000301020304050 where the first 16 bits are the PC bits from EPC
memory).
>>> modem.protocol.isoc.filter.1.length=64
>>> modem.protocol.isoc.filter.1.offset=16
>>> modem.protocol.isoc.filter.1.mask=3000301020304050
>>> modem.protocol.isoc.filter.1.action=assert_deassert
>>> modem.protocol.isoc.filter.1.enabled=1
>>> modem.protocol.isoc.filtering.truncated_epc_response=1
>>> modem.protocol.isoc.filtering.enabled=1
Type
Permissions
Data Type
Default
var
guest=-,admin=rw
bool
False
196 INfinity 510 Protocol Reference Guide