Offset for homing parameters can now be set to zero

instrumentkit · Mar 25, 2022 · b05b6c9 · b05b6c9
1 parent bd4fc9f
commit b05b6c9
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Showing 2 changed files with 59 additions and 1 deletion.
diff --git a/instruments/tests/test_thorlabs/test_thorlabs_apt.py b/instruments/tests/test_thorlabs/test_thorlabs_apt.py
@@ -1404,6 +1404,64 @@ def test_apt_mc_home_parameters_set_with_none(init_kdc101):
         apt.channel[0].home_parameters = None, None, None, None
 
 
+def test_apt_mc_home_parameters_set_offset_to_zero(init_kdc101):
+    """Ensure setting offset to zero is not interpreted as `None`."""
+    home_direction = 1
+    limit_switch = 1
+    velocity = 1000
+    offset = 1250
+    offset_new = 0
+    with expected_protocol(
+        ik.thorlabs.APTMotorController,
+        [
+            init_kdc101[0],
+            ThorLabsPacket(
+                message_id=ThorLabsCommands.MOT_REQ_HOMEPARAMS,
+                param1=0x01,
+                param2=0x00,
+                dest=0x50,
+                source=0x01,
+                data=None,
+            ).pack(),
+            ThorLabsPacket(
+                message_id=ThorLabsCommands.MOT_SET_HOMEPARAMS,
+                param1=None,
+                param2=None,
+                dest=0x50,
+                source=0x01,
+                data=struct.pack(
+                    "<HHHll",
+                    0x01,
+                    home_direction,
+                    limit_switch,
+                    velocity,
+                    offset_new,
+                ),
+            ).pack(),
+        ],
+        [
+            init_kdc101[1],
+            ThorLabsPacket(
+                message_id=ThorLabsCommands.MOT_GET_HOMEPARAMS,
+                param1=None,
+                param2=None,
+                dest=0x50,
+                source=0x01,
+                data=struct.pack(
+                    "<HHHll",
+                    0x01,
+                    home_direction,
+                    limit_switch,
+                    velocity,
+                    offset,
+                ),
+            ).pack(),
+        ],
+        sep="",
+    ) as apt:
+        apt.channel[0].home_parameters = None, None, None, offset_new
+
+
 def test_apt_mc_home_parameters(init_kdc101):
     """Get / set home_parameters in unitful fashion."""
     home_direction = 1

diff --git a/instruments/thorlabs/thorlabsapt.py b/instruments/thorlabs/thorlabsapt.py
@@ -1407,7 +1407,7 @@ def home_parameters(self, values):
             # replace values that are `None`
             if None in values:
                 set_params = self.home_parameters
-                values = [x if x else y for x, y in zip(values, set_params)]
+                values = [x if x is not None else y for x, y in zip(values, set_params)]
 
             home_dir, lim_sw, velocity, offset = values
             if isinstance(velocity, u.Quantity):