4 files changed, 65 insertions, 56 deletions

diff --git a/glucometerutils/drivers/otultraeasy.py b/glucometerutils/drivers/otultraeasy.py
index aafc2bd..1876402 100644
--- a/glucometerutils/drivers/otultraeasy.py
+++ b/glucometerutils/drivers/otultraeasy.py
@@ -30,12 +30,14 @@ from glucometerutils.support import lifescan
 from glucometerutils.support import lifescan_binary_protocol
 from glucometerutils.support import serial
 
+_PACKET = lifescan_binary_protocol.LifeScanPacket(
+    0x05, True)
 
 _INVALID_RECORD = 501
 
-_COMMAND_SUCCESS = construct.Const(b'\x05\x06')
+_COMMAND_SUCCESS = construct.Const(b'\x06')
 
-_VERSION_REQUEST = construct.Const(b'\x05\x0d\x02')
+_VERSION_REQUEST = construct.Const(b'\x0d\x02')
 
 _VERSION_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
@@ -43,7 +45,7 @@ _VERSION_RESPONSE = construct.Struct(
 )
 
 _SERIAL_NUMBER_REQUEST = construct.Const(
-    b'\x05\x0B\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+    b'\x0B\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00')
 
 _SERIAL_NUMBER_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
@@ -51,7 +53,7 @@ _SERIAL_NUMBER_RESPONSE = construct.Struct(
 )
 
 _DATETIME_REQUEST = construct.Struct(
-    construct.Const(b'\x05\x20'),  # 0x20 is the datetime
+    construct.Const(b'\x20'),  # 0x20 is the datetime
     'request_type' / construct.Enum(construct.Byte, write=0x01, read=0x02),
     'timestamp' / construct.Default(
         construct_extras.Timestamp(construct.Int32ul),
@@ -64,7 +66,7 @@ _DATETIME_RESPONSE = construct.Struct(
 )
 
 _GLUCOSE_UNIT_REQUEST = construct.Const(
-    b'\x05\x09\x02\x09\x00\x00\x00\x00')
+    b'\x09\x02\x09\x00\x00\x00\x00')
 
 
 _GLUCOSE_UNIT_RESPONSE = construct.Struct(
@@ -73,15 +75,15 @@ _GLUCOSE_UNIT_RESPONSE = construct.Struct(
     construct.Padding(3),
 )
 
-_MEMORY_ERASE_REQUEST = construct.Const(b'\x05\x1A')
+_MEMORY_ERASE_REQUEST = construct.Const(b'\x1A')
 
 _READING_COUNT_RESPONSE = construct.Struct(
-    construct.Const(b'\x05\x0f'),
+    construct.Const(b'\x0f'),
     'count' / construct.Int16ul,
 )
 
 _READ_RECORD_REQUEST = construct.Struct(
-    construct.Const(b'\x05\x1f'),
+    construct.Const(b'\x1f'),
     'record_id' / construct.Int16ul,
 )
 
@@ -102,7 +104,7 @@ class Device(serial.SerialDevice):
         self.sent_counter_ = False
         self.expect_receive_ = False
         self.buffered_reader_ = construct.Rebuffered(
-            lifescan_binary_protocol.PACKET, tailcutoff=1024)
+            _PACKET, tailcutoff=1024)
 
     def connect(self):
         try:
@@ -115,7 +117,7 @@ class Device(serial.SerialDevice):
         self.connect()
 
     def _send_packet(self, message, acknowledge=False, disconnect=False):
-        pkt = lifescan_binary_protocol.PACKET.build(
+        pkt = _PACKET.build(
             {'value': {
                 'message': message,
                 'link_control': {
diff --git a/glucometerutils/drivers/otverio2015.py b/glucometerutils/drivers/otverio2015.py
index 9aff4d2..5bc11dc 100644
--- a/glucometerutils/drivers/otverio2015.py
+++ b/glucometerutils/drivers/otverio2015.py
@@ -42,12 +42,13 @@ from glucometerutils.support import lifescan_binary_protocol
 _REGISTER_SIZE = 512
 
 _PACKET = construct.Padded(
-    _REGISTER_SIZE, construct.Embedded(lifescan_binary_protocol.PACKET))
+    _REGISTER_SIZE, construct.Embedded(
+        lifescan_binary_protocol.LifeScanPacket(0x03, False)))
 
-_COMMAND_SUCCESS = construct.Const(b'\x04\x06')
+_COMMAND_SUCCESS = construct.Const(b'\x06')
 
 _QUERY_REQUEST = construct.Struct(
-    construct.Const(b'\x04\xe6\x02'),
+    construct.Const(b'\xe6\x02'),
     'selector' / construct.Enum(
         construct.Byte, serial=0x00, model=0x01, software=0x02),
 )
@@ -59,18 +60,17 @@ _QUERY_RESPONSE = construct.Struct(
 )
 
 _READ_PARAMETER_REQUEST = construct.Struct(
-    construct.Const(b'\x04'),
     'selector' / construct.Enum(
         construct.Byte, unit=0x04),
 )
 
 _READ_UNIT_RESPONSE = construct.Struct(
-    construct.Const(b'\x03\x06'),  # different from _COMMAND_SUCCESS
+    _COMMAND_SUCCESS,
     'unit' / lifescan_binary_protocol.GLUCOSE_UNIT,
     construct.Padding(3),
 )
 
-_READ_RTC_REQUEST = construct.Const(b'\x04\x20\x02')
+_READ_RTC_REQUEST = construct.Const(b'\x20\x02')
 
 _READ_RTC_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
@@ -78,13 +78,13 @@ _READ_RTC_RESPONSE = construct.Struct(
 )
 
 _WRITE_RTC_REQUEST = construct.Struct(
-    construct.Const(b'\x04\x20\x01'),
+    construct.Const(b'\x20\x01'),
     'timestamp' / lifescan_binary_protocol.VERIO_TIMESTAMP,
 )
 
-_MEMORY_ERASE_REQUEST = construct.Const(b'\x04\x1a')
+_MEMORY_ERASE_REQUEST = construct.Const(b'\x1a')
 
-_READ_RECORD_COUNT_REQUEST = construct.Const(b'\x04\x27\x00')
+_READ_RECORD_COUNT_REQUEST = construct.Const(b'\x27\x00')
 
 _READ_RECORD_COUNT_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
@@ -92,7 +92,7 @@ _READ_RECORD_COUNT_RESPONSE = construct.Struct(
 )
 
 _READ_RECORD_REQUEST = construct.Struct(
-    construct.Const(b'\x04\x31\x02'),
+    construct.Const(b'\x31\x02'),
     'record_id' / construct.Int16ul,
     construct.Const(b'\x00'),
 )
@@ -161,7 +161,6 @@ class Device(object):
             request = request_format.build(request_obj)
             request_raw = _PACKET.build({'value': {
                 'message': request,
-                'link_control': {},  # Verio does not use link_control.
             }})
             logging.debug(
                 'Request sent: %s', binascii.hexlify(request_raw))
diff --git a/glucometerutils/drivers/otverioiq.py b/glucometerutils/drivers/otverioiq.py
index 9cd9e16..c4e70cf 100644
--- a/glucometerutils/drivers/otverioiq.py
+++ b/glucometerutils/drivers/otverioiq.py
@@ -24,9 +24,12 @@ from glucometerutils.support import lifescan
 from glucometerutils.support import lifescan_binary_protocol
 from glucometerutils.support import serial
 
-_COMMAND_SUCCESS = construct.Const(b'\x04\x06')
+_PACKET = lifescan_binary_protocol.LifeScanPacket(
+    0x03, True)
 
-_VERSION_REQUEST = construct.Const(b'\x04\x0d\x02')  # Untested
+_COMMAND_SUCCESS = construct.Const(b'\x06')
+
+_VERSION_REQUEST = construct.Const(b'\x0d\x02')  # Untested
 
 _VERSION_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
@@ -34,14 +37,14 @@ _VERSION_RESPONSE = construct.Struct(
 )
 
 _SERIAL_NUMBER_REQUEST = construct.Const(
-    b'\x04\x0b\x00\x02')
+    b'\x0b\x00\x02')
 
 _SERIAL_NUMBER_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
     'serial_number' / construct.CString(encoding='ascii'),
 )
 
-_READ_RTC_REQUEST = construct.Const(b'\x04\x20\x02')
+_READ_RTC_REQUEST = construct.Const(b'\x20\x02')
 
 _READ_RTC_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
@@ -49,12 +52,12 @@ _READ_RTC_RESPONSE = construct.Struct(
 )
 
 _WRITE_RTC_REQUEST = construct.Struct(
-    construct.Const(b'\x04\x20\x01'),
+    construct.Const(b'\x20\x01'),
     'timestamp' / lifescan_binary_protocol.VERIO_TIMESTAMP,
 )
 
 _GLUCOSE_UNIT_REQUEST = construct.Const(
-    b'\x04\x09\x02\x02')
+    b'\x09\x02\x02')
 
 
 _GLUCOSE_UNIT_RESPONSE = construct.Struct(
@@ -63,9 +66,9 @@ _GLUCOSE_UNIT_RESPONSE = construct.Struct(
     construct.Padding(3),
 )
 
-_MEMORY_ERASE_REQUEST = construct.Const(b'\x04\x1a')  # Untested
+_MEMORY_ERASE_REQUEST = construct.Const(b'\x1a')  # Untested
 
-_READ_RECORD_COUNT_REQUEST = construct.Const(b'\x04\x27\x00')
+_READ_RECORD_COUNT_REQUEST = construct.Const(b'\x27\x00')
 
 _READ_RECORD_COUNT_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
@@ -73,7 +76,7 @@ _READ_RECORD_COUNT_RESPONSE = construct.Struct(
 )
 
 _READ_RECORD_REQUEST = construct.Struct(
-    construct.Const(b'\x04\x21'),
+    construct.Const(b'\x21'),
     'record_id' / construct.Int16ul,
 )
 
diff --git a/glucometerutils/support/lifescan_binary_protocol.py b/glucometerutils/support/lifescan_binary_protocol.py
index 0143cd4..92a0002 100644
--- a/glucometerutils/support/lifescan_binary_protocol.py
+++ b/glucometerutils/support/lifescan_binary_protocol.py
@@ -18,36 +18,41 @@ from glucometerutils import common
 from glucometerutils.support import construct_extras
 from glucometerutils.support import lifescan
 
+_LINK_CONTROL = construct.BitStruct(
+    construct.Padding(3),
+    'more' / construct.Default(construct.Flag, False),
+    'disconnect' / construct.Default(construct.Flag, False),
+    'acknowledge' / construct.Default(construct.Flag, False),
+    'expect_receive' / construct.Default(construct.Flag, False),
+    'sequence_number' / construct.Default(construct.Flag, False),
+)
+
+def LifeScanPacket(command_prefix, include_link_control):
+    if include_link_control:
+        link_control_construct = _LINK_CONTROL
+    else:
+        link_control_construct = construct.Const(b'\x00')
 
-PACKET = construct.Struct(
-    construct.RawCopy(
-        construct.Embedded(
-            construct.Struct(
-                construct.Const(b'\x02'),  # stx
-                'length' / construct.Rebuild(
-                    construct.Byte, lambda ctx: len(ctx.message) + 6),
-                # The following structure is only used by some of the devices.
-                'link_control' / construct.BitStruct(
-                    construct.Padding(3),
-                    'more' / construct.Default(
-                        construct.Flag, False),
-                    'disconnect' / construct.Default(
-                        construct.Flag, False),
-                    'acknowledge' / construct.Default(
-                        construct.Flag, False),
-                    'expect_receive' / construct.Default(
-                        construct.Flag, False),
-                    'sequence_number' / construct.Default(
-                        construct.Flag, False),
+    command_prefix_construct = construct.Const(construct.Byte, command_prefix)
+
+    return construct.Struct(
+        construct.RawCopy(
+            construct.Embedded(
+                construct.Struct(
+                    construct.Const(b'\x02'),  # stx
+                    'length' / construct.Rebuild(
+                        construct.Byte, lambda ctx: len(ctx.message) + 7),
+                    'link_control' / link_control_construct,
+                    'command_prefix' / command_prefix_construct,
+                    'message' / construct.Bytes(
+                        length=lambda ctx: ctx.length - 7),
+                    construct.Const(b'\x03'),  # etx
                 ),
-                'message' / construct.Bytes(length=lambda ctx: ctx.length - 6),
-                construct.Const(b'\x03'),  # etx
             ),
         ),
-    ),
-    'checksum' / construct.Checksum(
-        construct.Int16ul, lifescan.crc_ccitt, construct.this.data),
-)
+        'checksum' / construct.Checksum(
+            construct.Int16ul, lifescan.crc_ccitt, construct.this.data),
+    )
 
 VERIO_TIMESTAMP = construct_extras.Timestamp(
     construct.Int32ul, epoch=946684800)  # 2010-01-01 00:00