The ThingMagic Mercury API is used to discover, provision and control ThingMagic RFID readers.
Reading RFID tags is as simple as this:
import mercury reader = mercury.Reader("tmr:///dev/ttyUSB0") reader.set_region("EU3") reader.set_read_plan([1], "GEN2") print(reader.read())Import the module mercury and create an mercury.Reader object.
import mercuryRepresents a connection to the reader.
Object constructor. Connects to the reader:
- uri identifies the device communication channel:
"tmr:///com2"is a typical format to connect to a serial based module on Windows COM2"tmr:///dev/ttyUSB0"is a typical format to connect to a USB device named ttyUSB0 on a Unix system"llrp://192.198.1.100"is a typical format to connect to an Ethernet device (works on Linux only)
- baudrate defines the desired communication speed. Supported values include 110, 300, 600, 1200, 2400, 4800, 9600, 14400, 19200, 38400, 57600 and 115200 (default).
For example:
reader = mercury.Reader("tmr:///dev/ttyUSB0", baudrate=9600)Returns the chip temperature in degrees of Celsius.
Lists supported regions for the connected device.
For example:
print(reader.get_supported_regions()) ['NA2', 'IN', 'JP', 'PRC', 'EU3', 'KR2', 'AU', 'NZ']Lists supported radio power range, in centidBm.
For example:
print(reader.get_power_range()) (0, 3000)Lists available antennas.
For example:
print(reader.get_antennas()) [1, 2]Lists configured read powers for each antenna. [(antenna, power)]
For example:
print(reader.get_read_powers()) [(1, 1800), (2, 3000)]Controls the Region of Operation for the connected device:
- region represents the regulatory region that the device will operate in. Supported values are:
"NA", North America/FCC"NA2""NA3""EU", European Union/ETSI EN 302 208"EU2", European Union/ETSI EN 300 220"EU3", European Union/ETSI Revised EN 302 208"IS", Israel"IN", India"JP", Japan"KR", Korea MIC"KR2", Korea KCC"PRC", China"PRC2""AU", Australia/AIDA LIPD Variation 2011"NZ", New Zealand
For example:
reader.set_region("EU3")Specifies the antennas and protocol to use for a search:
- antennas list define which antennas (or virtual antenna numbers) to use in the search
- protocol defines the protocol to search on. Supported values are:
"GEN2", UPC GEN2"ISO180006B", ISO 180006B"UCODE", ISO 180006B UCODE"IPX64", IPX (64kbps link rate)"IPX256", IPX (256kbps link rate)"ATA"
- bank defines the memory banks to read. Supported values are:
"reserved""epc""tid""user"
- read_power defines the transmit power, in centidBm, for read operations. If not given, a reader specific default value is used.
For example:
reader.set_read_plan([1], "GEN2")Set the read power for each listed antenna and return the real setted values. Setted values may differ from those passed due to reader rounding.
- antennas list define which antennas (or virtual antenna numbers) are going to be setted.
- powers list define the power, in centidBm, for each antenna. Overrides the value from set_read_plan or reader specific default.
- Power values must be within the allowed power range.
For example:
setted_powers = reader.set_read_powers([1, 2], [1533, 1912]) print(setted_powers) [(1, 1525), (2, 1900)]Performs a synchronous read, and then returns a list of TagReadData objects resulting from the search. If no tags were found then the list will be empty.
- timeout sets the reading time
For example:
print(reader.read()) [b'E2002047381502180820C296', b'0000000000000000C0002403']Performs a synchronous write and then returns a boolean indicating the success of the operation.
For example:
old_epc = 'E2002047381502180820C296' new_epc = 'E20020470000000000000012' reader = Reader('llrp://192.168.0.2') reader.set_read_plan([1], "GEN2") if reader.write(epc_target=old_epc, epc_code=new_epc): print('Rewrited "{}" with "{}"'.format(old_epc, new_epc)) else: print('Failed writing "{}" with "{}"'.format(old_epc, new_epc))Starts asynchronous reading. It returns immediately and begins a sequence of reads or a continuous read. The results are passed to the callback. The reads are repeated until the reader.stop_reading() method is called
- callback(TagReadData) will be invoked for every tag detected
- on_time sets the duration, in milliseconds, for the reader to be actively querying
- off_time duration, in milliseconds, for the reader to be quiet while querying
For example:
reader.start_reading(lambda tag: print(tag.epc)) b'E2002047381502180820C296' b'0000000000000000C0002403'Stops the asynchronous reading started by reader.start_reading().
For example:
reader.stop_reading()Returns a model identifier for the connected reader hardware.
For example:
print(reader.get_model()) M6e NanoRepresents a read of an RFID tag:
- epc corresponds to the Electronic Product Code
- antenna indicates where the tag was read
- read_count indicates how many times was the tag read during interrogation
- rssi is the strength of the signal recieved from the tag
- epc_mem_data contains the EPC bank data bytes
- tid_mem_data contains the TID bank data bytes
- user_mem_data contains the User bank data bytes
- reserved_mem_data contains the Reserved bank data bytes
The string representation (repr) of the tag data is its EPC.
Please note that the bank data bytes need to be requested via the bank parameter of the reader.set_read_plan function. Data not requested will not be read.
Use the Windows installer for the latest release and Python 3.6.
If you get the "ImportError: DLL load failed", make sure you have the Microsoft Visual C++ 2010 Redistributable Package installed.
To build an installer for other Python releases you need to:
- Download the latest Mercury API, e.g. mercuryapi-1.29.4.34.zip.
- Open mercuryapi-1.29.4.34/c/src/api/ltkc_win32/inc/stdint_win32.h and comment (or delete) the block of
typedefforint_fast8_tthroughuint_fast64_t(8 lines) - Download latest pthreads-win32 binaries (.dll and .lib) for your architecture
- Obtain Microsoft Visual Studio 2017, including the Python extensions
- Open the Solution and review the setup-win.py
- Verify the
mercuryapidirectory - Set
library_dirsanddata_filesto the pthreads-win32 you downloaded - Set Script Arguments to
bdist_wininst -p win32(default) orbdist_wininst -p amd64
- Verify the
- Start setup-win.py (without debugging)
First, make sure you have the required packages
yum install patch libxslt gcc readline-devel python-develor
apt-get install patch xsltproc gcc libreadline-dev python-devBoth Python 2.x and Python 3.x are supported. To use the Python 3.x you may need to install the python3-dev[evel] instead of the python-dev[evel] packages.
Build the module simply by running
cd python-mercuryapi makeThis will download and build the Mercury API SDK and then it will build the Python module itself.
The make command will automatically determine which Python version is installed. If both 2.x and 3.x are installed, the 3.x takes precedence. To build and install 2.x you need to explicitly specify the Python interpreter to use:
sudo make PYTHON=pythonThen, install the module by running
sudo make installwhich is a shortcut to running
sudo python setup.py installTo access ports like /dev/ttyUSB0 as a non-root user you may need to add this user to the dialout group:
sudo usermod -a -G dialout $USER