
ThingMagic M6e User Guide
35
Meta-data Control at Module Level
The meta-data selection information is transferred to the module and the module only reports desired
values, resulting in a small increase in performance under some circumstances. No additional configuration
parameters are necessary to take advantage of this feature.
Filtering on Tag Length and EPC Truncation
The Universal Reader Assistant can filter based on tag length and EPC truncation:
•
Only return tags if the EPC is of the expected length, which weeds out stray and phantom tags.
•
Only announces tags whose EPCs contain a certain beginning value and length. The desired EPC value
includes both the PC word (which gives the EPC length) and the desired starting value for EPC. Tags
do not respond if they do not have that start value and length; they only respond with the unique portion
of their EPC (not the shared prefix value) to increase performance.
Note that “EPC Truncate” is difficult to distinguish between a normal filter on EPC ID because the part of
the EPC that is not reported by the tag is appended to the EPC as reported in the tag results screen.
Power Management
The M6e is designed for power efficiency and offers several different power management modes. The
following power management modes affect the power consumption during different periods of M6e usage
and impact performance in different ways. The available power management modes are:
•
- Set in /reader/powerMode. Controls the power savings when the M6e is idle.
•
Transmit Modes - Set in /reader/radio/enablePowerSave. Controls power savings while transmitting.
Power Modes
The Power Mode setting (set in /reader/powerMode) allows the user to trade off increased RF operation
startup time for additional power savings. The details of the amount of power consumed in each mode is
shown in the table under
. The behavior of each mode and impact on RF
command latency is as follows:
•
PowerMode.FULL
– In this mode, the unit operates at full power to attain the best performance
possible. This mode is only intended for use in cases where power consumption is not an issue. This is
the default Power Mode at startup.
•
PowerMode.MINSAVE
– This mode performs more aggressive power savings, such as automatically
shutting down the analog section between commands, and then restarting it whenever a tag command
is issued. This mode may add up to 50 ms of delay from idle to RF on when initiating an RF operation.
•
PowerMode.SLEEP
– This mode essentially shuts down the digital and analog boards, except to power
the bare minimum logic required to wake the processor. This mode may add up to 100 ms of delay from
idle to RF on when initiating an RF operation.
PowerMode.SLEEP is not supported when using the
USB interface
. Using the setting PowerMode.MEDSAVE is the same as SLEEP.
NOTE: See additional latency specifications under
Transmit Modes
The Transmit Mode setting (set in /reader/radio/enablePowerSave) allows the user to trade off RF spectral
compliance with the Gen2 DRM Mask for increased power savings while transmitting. The details of the
amount of power consumed in each mode is shown in the table under
of each mode is as follows: