# -*- coding: utf-8 -*-
"""Driver for LifeScan OneTouch Ultra 2 devices"""
__author__ = 'Diego Elio Pettenò'
__email__ = 'flameeyes@flameeyes.eu'
__copyright__ = 'Copyright © 2013, Diego Elio Pettenò'
__license__ = 'MIT'
import datetime
import re
import serial
from glucometerutils import common
from glucometerutils import exceptions
from glucometerutils.drivers import lifescan_common
# The following two hashes are taken directly from LifeScan's documentation
_MEAL_CODES = {
'N': common.NO_MEAL,
'B': common.BEFORE_MEAL,
'A': common.AFTER_MEAL,
}
_COMMENT_CODES = {
'00': '', # would be 'No Comment'
'01': 'Not Enough Food',
'02': 'Too Much Food',
'03': 'Mild Exercise',
'04': 'Hard Exercise',
'05': 'Medication',
'06': 'Stress',
'07': 'Illness',
'08': 'Feel Hypo',
'09': 'Menses',
'10': 'Vacation',
'11': 'Other',
}
_DUMP_HEADER_RE = re.compile(
r'P ([0-9]{3}),"[0-9A-Z]{9}","(?:MG/DL |MMOL/L)"')
_DUMP_LINE_RE = re.compile(
r'P (?P<datetime>"[A-Z]{3}","[0-9/]{8}","[0-9:]{8} "),'
r'"(?P<control>[C ]) (?P<value>[0-9]{3})(?P<parityerror>[\? ])",'
r'"(?P<meal>[NBA])","(?P<comment>0[0-9]|1[01])", 00')
_RESPONSE_MATCH = re.compile(r'^(.+) ([0-9A-F]{4})\r$')
def _calculate_checksum(bytestring):
"""Calculate the checksum used by OneTouch Ultra and Ultra2 devices
Args:
bytestring: the string of which the checksum has to be calculated.
Returns:
A string with the hexdecimal representation of the checksum for the input.
The checksum is a very stupid one: it just sums all the bytes,
modulo 16-bit, without any parity.
"""
checksum = 0
for byte in bytestring:
checksum = (checksum + byte) & 0xffff
return checksum
def _validate_and_strip_checksum(line):
"""Verify the simple 16-bit checksum and remove it from the line.
Args:
line: the line to check the checksum of.
Returns:
A copy of the line with the checksum stripped out.
"""
match = _RESPONSE_MATCH.match(line)
if not match:
raise lifescan_common.MissingChecksum(line)
response, checksum_string = match.groups()
try:
checksum_given = int(checksum_string, 16)
checksum_calculated = _calculate_checksum(
bytes(response, 'ascii'))
if checksum_given != checksum_calculated:
raise exceptions.InvalidChecksum(checksum_given,
checksum_calculated)
except ValueError:
raise exceptions.InvalidChecksum(checksum_given, None)
return response
_DATETIME_RE = re.compile(
r'^"[A-Z]{3}","([0-9]{2}/[0-9]{2}/[0-9]{2})","([0-9]{2}:[0-9]{2}:[0-9]{2}) "$')
def _parse_datetime(response):
"""Convert a response with date and time from the meter into a datetime.
Args:
response: the response coming from a DMF or DMT command
Returns:
A datetime object built according to the returned response.
Raises:
InvalidResponse if the string cannot be matched by _DATETIME_RE.
"""
match = _DATETIME_RE.match(response)
if not match:
raise exceptions.InvalidResponse(response)
date, time = match.groups()
month, day, year = map(date.split('/'), int)
hour, minute, second = map(time.split(':'), int)
# Yes, OneTouch2's firmware is not Y2K safe.
return datetime.datetime(2000 + year, month, day, hour, minute, second)
class Device(object):
def __init__(self, device):
self.serial_ = serial.Serial(
port=device, baudrate=9600, bytesize=serial.EIGHTBITS,
parity=serial.PARITY_NONE, stopbits=serial.STOPBITS_ONE,
timeout=1, xonxoff=False, rtscts=False, dsrdtr=False, writeTimeout=None)
def connect(self):
return
def disconnect(self):
return
def _send_command(self, cmd):
"""Send command interface.
Args:
cmd: command and parameters to send (without newline)
"""
cmdstring = bytes('\x11\r' + cmd + '\r', 'ascii')
self.serial_.write(cmdstring)
self.serial_.flush()
def _send_oneliner_command(self, cmd):
"""Send command and read a one-line response.
Args:
cmd: command and parameters to send (without newline)
Returns:
A single line of text that the glucometer responds, without the checksum.
"""
self._send_command(cmd)
line = self.serial_.readline().decode('ascii')
return _validate_and_strip_checksum(line)
def get_information_string(self):
"""Returns a single string with all the identification information.
Returns:
A string including the serial number, software version, date and time and
default unit.
"""
return ('OneTouch Ultra 2 glucometer\n'
'Serial number: %s\n'
'Software version: %s\n'
'Time: %s\n'
'Default unit: %s' % (
self.get_serial_number(),
self.get_version(),
self.get_datetime(),
self.get_glucose_unit()))
def get_version(self):
"""Returns an identifier of the firmware version of the glucometer.
Returns:
The software version returned by the glucometer, such as
"P02.00.00 30/08/06".
"""
response = self._send_oneliner_command('DM?')
if response[0] != '?':
raise exceptions.InvalidResponse(response)
return response[1:]
_SERIAL_NUMBER_RE = re.compile('^@ "([A-Z0-9]{9})"$')
def get_serial_number(self):
"""Retrieve the serial number of the device.
Returns:
A string representing the serial number of the device.
Raises:
exceptions.InvalidResponse: if the DM@ command returns a string not
matching _SERIAL_NUMBER_RE.
InvalidSerialNumber: if the returned serial number does not match
the OneTouch2 device as per specs.
"""
response = self._send_oneliner_command('DM@')
match = self._SERIAL_NUMBER_RE.match(response)
if not match:
raise exceptions.InvalidResponse(response)
serial_number = match.group(1)
# 'Y' at the far right of the serial number is the indication of a OneTouch
# Ultra2 device, as per specs.
if serial_number[-1] != 'Y':
raise lifescan_common.InvalidSerialNumber(serial_number)
return serial_number
def get_datetime(self):
"""Returns the current date and time for the glucometer.
Returns:
A datetime object built according to the returned response.
"""
response = self._send_oneliner_command('DMF')
return _parse_datetime(response[2:])
def set_datetime(self, date=datetime.datetime.now()):
"""Sets the date and time of the glucometer.
Args:
date: The value to set the date/time of the glucometer to. If none is
given, the current date and time of the computer is used.
Returns:
A datetime object built according to the returned response.
"""
response = self._send_oneliner_command(
'DMT' + date.strftime('%m/%d/%y %H:%M:%S'))
return _parse_datetime(response[2:])
def zero_log(self):
"""Zeros out the data log of the device.
This function will clear the memory of the device deleting all the readings
in an irrecoverable way.
"""
response = self._send_oneliner_command('DMZ')
if response != 'Z':
raise exceptions.InvalidResponse(response)
_GLUCOSE_UNIT_RE = re.compile(r'^SU\?,"(MG/DL |MMOL/L)"')
def get_glucose_unit(self):
"""Returns a constant representing the unit displayed by the meter.
Returns:
common.UNIT_MGDL: if the glucometer displays in mg/dL
common.UNIT_MMOLL: if the glucometer displays in mmol/L
Raises:
exceptions.InvalidGlucoseUnit: if the unit is not recognized
OneTouch meters will always dump data in mg/dL because that's their internal
storage. They will then provide a separate method to read the unit used for
display. This is not settable by the user in all modern meters.
"""
response = self._send_oneliner_command('DMSU?')
match = self._GLUCOSE_UNIT_RE.match(response)
unit = match.group(1)
if unit == 'MG/DL ':
return common.UNIT_MGDL
elif unit == 'MMOL/L':
return common.UNIT_MMOLL
else:
raise exceptions.InvalidGlucoseUnit(string)
def get_readings(self):
"""Iterates over the reading values stored in the glucometer.
Args:
unit: The glucose unit to use for the output.
Yields:
A tuple (date, value) of the readings in the glucometer. The value is a
floating point in the unit specified; if no unit is specified, the default
unit in the glucometer will be used.
Raises:
exceptions.InvalidResponse: if the response does not match what expected.
"""
self._send_command('DMP')
data = self.serial_.readlines()
header = data.pop(0).decode('ascii')
match = _DUMP_HEADER_RE.match(header)
if not match:
raise exceptions.InvalidResponse(header)
count = int(match.group(1))
assert count == len(data)
for line in data:
line = _validate_and_strip_checksum(line.decode('ascii'))
match = _DUMP_LINE_RE.match(line)
if not match:
raise exceptions.InvalidResponse(line)
line_data = match.groupdict()
date = _parse_datetime(line_data['datetime'])
meal = _MEAL_CODES[line_data['meal']]
comment = _COMMENT_CODES[line_data['comment']]
# OneTouch2 always returns the data in mg/dL even if the glucometer is set
# to mmol/L, so there is no conversion required.
yield common.Reading(
date, float(line_data['value']), meal=meal, comment=comment)
