gnetplus Module

Module for interfacing with the PROMAG card reader using the GNetPlus® Protocol.

Usage:

>>> from gnetplus import Handle
>>> handle = Handle("/dev/ttyUSB0")
>>> print "S/N: " + hex(handle.get_sn())

exception gnetplus.GNetPlusError

Bases: exceptions.Exception

Exception thrown when receiving a ResponseMessage with function = ResponseMessage.NAK

class gnetplus.Handle(port, baudrate=19200, deviceaddr=0)

Bases: object

Main class used for interfacing with the card reader.

Parameters:

• port – String containing name of serial port, e.g. /dev/ttyUSB0
• baudrate – Baudrate for interfacing with the device. Don’t change this unless you know what you’re doing.
• deviceaddr – Integer containing the device address. Defaults to 0.

get_sn()

Get serial number of the card currently scanned.

Returns:16-bit integer containing serial number of the scanned card.

get_version()

Get product version string. May contain null bytes, so be careful when using it.

Returns:Product version string of the device connected to this handle.

readmsg(sink_events=False)

Reads a message, optionally ignoring event (EVN) messages which are device-driven.

Parameters:sink_events – Boolean dictating whether or not events should be ignored.

sendmsg(function, data='')

Constructs and sends a QueryMessage to the device

Parameters:

• function (int) – message function (0-255, see Message.function)
• data (str) – message data

set_auto_mode(enabled=True)

Toggle auto mode, i.e. whether the device emits events when a card comes close.

Parameters:enabled – Whether to enable or disable auto mode.

wait_for_card()

Block until card is present at the device. Does not check if a card is already present before entering the function.

exception gnetplus.InvalidMessage

Bases: exceptions.Exception

class gnetplus.Message(address=0, function=None, data='')

Bases: object

Base message class for representing a message

Parameters:

• address (int) – Device Address (0-255, default 0)
• function (int) – Function of this message
• data (str) – Payload of this message

SOH = 1

static gencrc(msgstr)

Generate CRC for the string msgstr

Parameters:msgstr – string containing data to be checksummed Returns:16-bit integer containing CRC checksum

classmethod readfrom(serial)

Constructs one message from serial

Parameters:serial – serial.Serial interface to read message from Return type:Message instance

sendto(serial)

Sends this message to serial

Parameters:serial (serial.Serial) – Serial interface to send this message to

class gnetplus.QueryMessage(address=0, function=None, data='')

Bases: gnetplus.Message

A query message to be sent from host machine to card reader device. Magical constants taken from protocol documentation.

ACCESS_CONDITION = 41

ADD_RECORD = 15

ANALOG_INPUT = 19

ANTI_COLLISION = 33

AUTHENTICATE = 35

AUTHENTICATE_KEY = 46

AUTO_MODE = 63

CLASSNAME = 6

CREATE_VALUE_BLOCK = 40

DEBUG = 29

DI = 18

DO = 17

ECHO = 24

ENABLE_AUTO_MODE = 25

ERASE_ALL_RECORDS = 14

GET_ACCESS_CONDITION = 45

GET_DATETIME = 8

GET_FIRST_RECORD = 12

GET_NEXT_RECORD = 13

GET_NODE = 21

GET_REGISTER = 9

GET_SECOND_SN = 44

GET_SECTOR = 61

GET_SN = 22

GET_TIME_ADJUST = 26

GET_VERSION = 1

GO_TO_ISP = 31

HALT = 42

LOGOFF = 4

LOGON = 3

POLLING = 0

READ_BLOCK = 36

READ_VALUE = 39

RECORD_COUNT = 11

RECOVER_ALL_RECORDS = 16

REQUEST = 32

REQUEST_ALL = 47

RESERVE = 24

RESET = 30

RESTORE = 52

RF_POWER_ONOFF = 62

SAVE_KEY = 43

SELECT_CARD = 34

SET_DATETIME = 7

SET_PASSWORD = 5

SET_REGISTER = 10

SET_SLAVE_ADDR = 2

SET_TIME_ADJUST = 28

SET_VALUE = 38

SET_VALUEEX = 50

SILENT_MODE = 23

THERMOMETER = 20

TRANSFER = 51

WRITE_BLOCk = 37

class gnetplus.ResponseMessage(address=0, function=None, data='')

Bases: gnetplus.Message

Message received from card reader

ACK = 6

EVN = 18

NAK = 21

to_error()

Construct a GNetPlusError for NAK response.

Returns:Constructed instance of GNetPlusError for this response