ThingMagic M6e User Guide
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“Untraceable”. Ability to limit reading of all or part of EPC, TID and User memory fields by unauthorized
readers.
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Ability to download and activate security keys.
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A
bility to authenticate tag using random challenge strings and AES encryption.
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Ability to obtain memory data in encrypted form, which can be successfully decoded if the host knows
the key that has been activated on the tag.
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Ability to obtain authentication and encrypted memory data from a tag buffer rather than the tag
backscattering that information to the reader immediately.
These capabilities are supported in the 1.27 version of the API and may be demonstrated using code
samples and the version of Universal Reader Assistant which is distributed with the API.
Denatran Tag Support
The M6e module supports the Denatran extension to the Gen2 protocol as a licensed feature.
Configurable T4 for Gen2 Protocol
Some sensor tags use a Select command to trigger sensor reading. The time the reader waits between the
Select command and start of inventory (when the Query command is sent) is controlled by a Gen2
parameter called the “T4 timer.” This has been updated so that the T4 timer can be set to a larger value to
ensure sufficient time for the sensor tag to obtain its reading before having to report it to the reader.
The parameter ‘PROTOCOL_PARAM_GEN2_T4’ has been added to set/get the Gen2 T4 parameter with
sub command for 0x9b and allows T4 to be set in milliseconds.
T4 value is 4-byte in length and specified in milliseconds. Minimum value of T4 allowed for 250 kHz (25us,
12.5us, 62.5us Tari) is 440usec (0x1B8) and for 640 kHz (6.25us Tari) is 220usec (0xDC). Maximum value
allowed is 1sec (0xF4240). Here is an oscilloscope trace of the reader output signal showing the effect of
changing this setting.