3 files changed, 11 insertions, 13 deletions
diff --git a/glucometerutils/drivers/otultraeasy.py b/glucometerutils/drivers/otultraeasy.py
index 0063ec1..fe7e4ae 100644
--- a/glucometerutils/drivers/otultraeasy.py
+++ b/glucometerutils/drivers/otultraeasy.py
@@ -66,15 +66,10 @@ _DATETIME_RESPONSE = construct.Struct(
 _GLUCOSE_UNIT_REQUEST = construct.Const(
     b'\x05\x09\x02\x09\x00\x00\x00\x00')
 
-_GLUCOSE_MAPPING = {
-    common.Unit.MG_DL: 0x00,
-    common.Unit.MMOL_L: 0x01,
-}
 
 _GLUCOSE_UNIT_RESPONSE = construct.Struct(
     _COMMAND_SUCCESS,
-    'unit' / construct.SymmetricMapping(
-        construct.Byte, _GLUCOSE_MAPPING),
+    'unit' / lifescan_binary_protocol.GLUCOSE_UNIT,
     construct.Padding(3),
 )
 
diff --git a/glucometerutils/drivers/otverio2015.py b/glucometerutils/drivers/otverio2015.py
index d0b8a9c..9aff4d2 100644
--- a/glucometerutils/drivers/otverio2015.py
+++ b/glucometerutils/drivers/otverio2015.py
@@ -64,15 +64,9 @@ _READ_PARAMETER_REQUEST = construct.Struct(
         construct.Byte, unit=0x04),
 )
 
-_GLUCOSE_MAPPING = {
-    common.Unit.MG_DL: 0x00,
-    common.Unit.MMOL_L: 0x01,
-}
-
 _READ_UNIT_RESPONSE = construct.Struct(
     construct.Const(b'\x03\x06'),  # different from _COMMAND_SUCCESS
-    'unit' / construct.SymmetricMapping(
-        construct.Byte, _GLUCOSE_MAPPING),
+    'unit' / lifescan_binary_protocol.GLUCOSE_UNIT,
     construct.Padding(3),
 )
 
diff --git a/glucometerutils/support/lifescan_binary_protocol.py b/glucometerutils/support/lifescan_binary_protocol.py
index 68b030d..0143cd4 100644
--- a/glucometerutils/support/lifescan_binary_protocol.py
+++ b/glucometerutils/support/lifescan_binary_protocol.py
@@ -14,6 +14,7 @@ __license__ = 'MIT'
 
 import construct
 
+from glucometerutils import common
 from glucometerutils.support import construct_extras
 from glucometerutils.support import lifescan
 
@@ -50,3 +51,11 @@ PACKET = construct.Struct(
 
 VERIO_TIMESTAMP = construct_extras.Timestamp(
     construct.Int32ul, epoch=946684800)  # 2010-01-01 00:00
+
+_GLUCOSE_UNIT_MAPPING_TABLE = {
+    common.Unit.MG_DL: 0x00,
+    common.Unit.MMOL_L: 0x01,
+}
+
+GLUCOSE_UNIT = construct.SymmetricMapping(
+    construct.Byte, _GLUCOSE_UNIT_MAPPING_TABLE)