Skip to content

Latest commit

 

History

History
92 lines (63 loc) · 3.02 KB

sense.rst

File metadata and controls

92 lines (63 loc) · 3.02 KB

sense.py

The sense example demonstrates the use of the :meth:`nfc.clf.ContactlessFrontend.sense` method to discover contactless targets.

$ sense.py [target [target ...]] [options]

The target arguments define the type, bitrate and optional attributes for the contactless targets that may be discovered in a single sense loop. An empty loop (no targets) is allowed but is only useful to verify the :meth:`nfc.clf.ContactlessFrontend.sense` method behavior. Optional arguments allow to set an iteration count and interval, continously repeat the (iterated) loop after a wait time, activate standard or verbose debug logs, and to specify the local device to use.

A target is specified by bitrate and a type identifier A, B, F. The following example would first sense for a DEP Target at 106kbps (in active communication mode), then for a Type A Target at 106 kbps, a Type B Target at 106kbps and a Type F Target at 212kbps.

$ sense.py 106A 106B 212F

Additional parameters can be supplied as comma-delimited name=value pairs in brackets. The example below searches for a 106 kbps DEP Target (in active communication mode) and then changes communication speed to 424 kbps.

$ sense.py '106A(atr_req=d400FFFFFFFFFFFFFFFF62260000003246666d010110)'

$ sense.py 106A --atr d400FFFFFFFFFFFFFFFF62260000003246666d010110

Options

.. option:: -h, --help

   Show a help message and exit.


.. option:: --dep params

   Attempt a DEP Target activation in passive communication mode when
   an appropriate Type A or Type F Target was discovered in in the
   main sense loop. The *params* argument defines optional attributes
   for the :class:`nfc.clf.DEP` target object. The example below would
   try a DEP Target activation (in passive communication mode) with a
   parameter change to 424 kbps after 106 kbps Type A Target
   discovery. ::

     $ sense.py 106A --dep 'psl_req=D404001203'


.. option:: -i number

   Specifies the number of iterations to run (default is 1
   iteration). Each iteration is a sense for all the targets given as
   positional arguments.


.. option:: -t seconds

   The time between two iterations (default is 0.2 sec). It is
   measured from the start of one iteration to the start of the next
   iteration, effectively it will thus never be shorter than the
   execution time of an iteration.


.. option:: -r, --repeat

   Forever repeat the sense loop (including the number of
   iterations). Execution can be terminated with Ctrl-C.


.. option:: -w seconds

   Wait the specified number of seconds between repetitions (the
   default wait time is 0.1 sec).


.. option:: -d, --debug

   Activate debug log messages on standard error output.


.. option:: -v, --verbose

   Activate more debug log messages, most notably all commands send to
   the local device will be logged as well as their responses.


.. option:: --device path

   Specify a local device search path (the default is ``usb``). For device
   path construction rules see :meth:`nfc.clf.ContactlessFrontend.open`.