1 files changed, 226 insertions, 0 deletions

diff --git a/glucometerutils/drivers/otverio2015.py b/glucometerutils/drivers/otverio2015.py
new file mode 100644
index 0000000..44f3573
--- /dev/null
+++ b/glucometerutils/drivers/otverio2015.py
@@ -0,0 +1,226 @@
+# -*- coding: utf-8 -*-
+"""Driver for LifeScan OneTouch Verio 2015 devices.
+
+Further information on the device protocol can be found at
+
+https://github.com/Flameeyes/glucometer-protocols/blob/master/lifescan/onetouch-verio-2015.md
+"""
+
+__author__ = 'Diego Elio Pettenò'
+__email__ = 'flameeyes@flameeyes.eu'
+__copyright__ = 'Copyright © 2016, Diego Elio Pettenò'
+__license__ = 'MIT'
+
+import datetime
+import struct
+
+from pyscsi.pyscsi.scsi import SCSI
+from pyscsi.pyscsi.scsi_device import SCSIDevice
+
+from glucometerutils import common
+from glucometerutils import exceptions
+from glucometerutils.drivers import lifescan_common
+
+# Match the same values in the otultraeasy driver.
+_STX = 0x02
+_ETX = 0x03
+
+# This device uses SCSI blocks as registers.
+_REGISTER_SIZE = 512
+
+_STRUCT_PREAMBLE = struct.Struct('<BH')
+_STRUCT_CODA = _STRUCT_PREAMBLE  # they are actually the same, mirrored.
+
+_STRUCT_UINT16 = struct.Struct('<H')
+_STRUCT_UINT32 = struct.Struct('<I')
+
+_STRUCT_CHECKSUM = _STRUCT_UINT16
+_STRUCT_TIMESTAMP = _STRUCT_UINT32
+_STRUCT_RECORDID = _STRUCT_UINT16
+_STRUCT_READING = _STRUCT_UINT32
+_STRUCT_RECORD = struct.Struct('<BBHBHIIBBB')
+
+_QUERY_REQUEST = b'\x04\xe6\x02'
+_QUERY_KEY_SERIAL = b'\x00'
+_QUERY_KEY_MODEL = b'\x01'
+_QUERY_KEY_SOFTWARE = b'\x02'
+
+_READ_RTC_REQUEST = b'\x04\x20\x02'
+_WRITE_RTC_REQUEST = b'\x04\x20\x01'
+# All timestamp reported by this device are seconds since this date.
+_EPOCH_BASE = 946684800  # 2010-01-01 00:00
+
+_READ_RECORD_COUNT_REQUEST = b'\x04\x27\x00'
+_READ_RECORD_REQUEST_PREFIX = b'\x04\x31\x02'
+_READ_RECORD_REQUEST_SUFFIX = b'\x00'
+
+_MEMORY_ERASE_REQUEST = b'\x04\x1a'
+
+def _extract_message(register):
+  """Parse the message preamble and verify checksums."""
+  stx, length = _STRUCT_PREAMBLE.unpack_from(register)
+  if stx != _STX:
+    raise lifescan_common.MalformedCommand(
+      'invalid STX byte: %02x' % stx)
+  if length > _REGISTER_SIZE:
+    raise lifescan_common.MalformedCommand(
+      'invalid length: %d > REGISTER_SIZE' % length)
+
+  # 2 is the length of the checksum, so it should be ignored.
+  calculated_checksum = lifescan_common.crc_ccitt(register[:(length-2)])
+
+  coda_offset = length - _STRUCT_CODA.size
+  etx, encoded_checksum = _STRUCT_CODA.unpack_from(register[coda_offset:])
+  if etx != _ETX:
+    raise lifescan_common.MalformedCommand(
+      'invalid ETX byte: %02x' % etx)
+  if encoded_checksum != calculated_checksum:
+    raise lifescan_common.InvalidChecksum(
+      encoded_checksum, calculated_checksum)
+
+  response = register[_STRUCT_PREAMBLE.size:coda_offset]
+  return response
+
+def _encode_message(cmd):
+  """Add message preamble and calculate checksum, add padding."""
+  length = len(cmd) + _STRUCT_PREAMBLE.size + _STRUCT_CODA.size
+  preamble = _STRUCT_PREAMBLE.pack(_STX, length)
+  message = preamble + cmd + bytes((_ETX,))
+  checksum = _STRUCT_CHECKSUM.pack(lifescan_common.crc_ccitt(message))
+
+  # Pad the message to match the size of the register.
+  return message + checksum + bytes(
+    _REGISTER_SIZE - 2 - len(message))
+
+def _convert_timestamp(timestamp):
+  return datetime.datetime.fromtimestamp(timestamp + _EPOCH_BASE)
+
+class Device(object):
+  def __init__(self, device):
+    self.device_name_ = device
+    self.scsi_device_ = SCSIDevice(device)
+    self.scsi_ = SCSI(self.scsi_device_)
+    self.scsi_.blocksize = _REGISTER_SIZE
+
+  def _send_message(self, cmd, lba):
+    """Send a request to the meter, and read its response.
+
+    Args:
+      cmd: (bytes) the raw command to send the device, without
+        preamble or checksum.
+      lba: (int) the address of the block register to use, known
+        valid addresses are 3, 4 and 5.
+
+    Returns:
+      (bytes) The raw response from the meter. No preamble or coda is
+      present, and the checksum has already been validated.
+    """
+    self.scsi_.write10(lba, 1, _encode_message(cmd))
+    response = self.scsi_.read10(lba, 1)
+    # TODO: validate that the response is valid.
+    return _extract_message(response.datain)
+
+  def connect(self):
+    inq = self.scsi_.inquiry()
+    vendor = inq.result['t10_vendor_identification'][:32]
+    if vendor != b'LifeScan':
+      raise exceptions.ConnectionFailed(
+        'Device %s is not a LifeScan glucometer.' % self.device_name_)
+
+  def disconnect(self):
+    return
+
+  def get_information_string(self):
+    return ('OneTouch %s glucometer\n'
+            'Serial number: %s\n'
+            'Software version: %s\n'
+            'Time: %s\n'
+            'Default unit: unknown\n' % (
+              self._query_string(_QUERY_KEY_MODEL),
+              self.get_serial_number(),
+              self.get_version(),
+              self.get_datetime()))
+
+  def _query_string(self, query_key):
+    response = self._send_message(_QUERY_REQUEST + query_key, 3)
+    if response[0:2] != b'\x04\06':
+      raise lifescan_common.MalformedCommand(
+        'invalid response, expected 04 06, received %02x %02x' % (
+          response[0], response[1]))
+    # Strings are encoded in wide characters (LE), but they should
+    # only contain ASCII characters. Note that the string is
+    # null-terminated, so the last character should be dropped.
+    return response[2:].decode('utf-16-le')[:-1]
+
+  def get_serial_number(self):
+    return self._query_string(_QUERY_KEY_SERIAL)
+
+  def get_version(self):
+    return self._query_string(_QUERY_KEY_SOFTWARE)
+
+  def get_datetime(self):
+    response = self._send_message(_READ_RTC_REQUEST, 3)
+    if response[0:2] != b'\x04\06':
+      raise lifescan_common.MalformedCommand(
+        'invalid response, expected 04 06, received %02x %02x' % (
+          response[0], response[1]))
+    (timestamp,) = _STRUCT_TIMESTAMP.unpack(response[2:])
+    return _convert_timestamp(timestamp)
+
+  def set_datetime(self, date=datetime.datetime.now()):
+    epoch = datetime.datetime.utcfromtimestamp(_EPOCH_BASE)
+    delta = date - epoch
+    timestamp = int(delta.total_seconds())
+
+    timestamp_bytes = _STRUCT_TIMESTAMP.pack(timestamp)
+    response = self._send_message(_WRITE_RTC_REQUEST + timestamp_bytes, 3)
+
+    if response[0:2] != b'\x04\06':
+      raise lifescan_common.MalformedCommand(
+        'invalid response, expected 04 06, received %02x %02x' % (
+          response[0], response[1]))
+
+    # The device does not return the new datetime, so confirm by
+    # calling READ RTC again.
+    return self.get_datetime()
+
+  def zero_log(self):
+    response = self._send_message(_MEMORY_ERASE_REQUEST, 3)
+    if response[0:2] != b'\x04\06':
+      raise lifescan_common.MalformedCommand(
+        'invalid response, expected 04 06, received %02x %02x' % (
+          response[0], response[1]))    
+
+  def _get_reading_count(self):
+    response = self._send_message(_READ_RECORD_COUNT_REQUEST, 3)
+    if response[0:2] != b'\x04\06':
+      raise lifescan_common.MalformedCommand(
+        'invalid response, expected 04 06, received %02x %02x' % (
+          response[0], response[1]))
+
+    (record_count,) = _STRUCT_RECORDID.unpack(response[2:])
+    return record_count
+
+  def get_glucose_unit(self):
+    return common.UNIT_MGDL
+
+  def _get_reading(self, record_number):
+    request = (_READ_RECORD_REQUEST_PREFIX +
+               _STRUCT_RECORDID.pack(record_number) +
+               _READ_RECORD_REQUEST_SUFFIX)
+    response = self._send_message(request, 3)
+    if response[0:2] != b'\x04\06':
+      raise lifescan_common.MalformedCommand(
+        'invalid response, expected 04 06, received %02x %02x' % (
+          response[0], response[1]))
+
+    (unused_const1, unused_const2, unused_counter, unused_const3,
+     unused_counter2, timestamp, value, unused_flags, unused_const4,
+     unused_const5) = _STRUCT_RECORD.unpack(response)
+
+    return common.Reading(_convert_timestamp(timestamp), float(value))
+
+  def get_readings(self):
+    record_count = self._get_reading_count()
+    for record_number in range(record_count):
+      yield self._get_reading(record_number)