[feat] gui sparc: if laser interlock is triggered, also blank the beam

One of the most common reason for the laser interlock to be triggered
is that the user opened the SPARC ATM cover. The inside of the ATM can
receive X-rays caused by the e-beam. So, to be extra safe, also blank
the e-beam whenever the laser interlock is triggered.

src/odemis/gui/cont/acquisition/sparc_acq.py

@@ -67,6 +67,12 @@ def __init__(self, tab_data, tab_panel, streambar_controller):
         self._tab_panel = tab_panel
         self._streambar_controller = streambar_controller
         self._interlockTriggered = False  # local/private bool to track interlock status
+        if self._main_data_model.ebeam and model.hasVA(self._main_data_model.ebeam, "blanker"):
+            # blanker state before interlock (to restore it when interlock is reset)
+            self._ebeam_blanker = self._main_data_model.ebeam.blanker
+            self._pre_interlock_blanker = self._ebeam_blanker.value
+        else:
+            self._ebeam_blanker = None
 
         if model.hasVA(self._main_data_model.light, "interlockTriggered"):
             # subscribe to the VA and initialize the warning status
@@ -217,33 +223,45 @@ def on_change_file(self, evt):
             self.conf.fn_ptn, self.conf.fn_count = guess_pattern(new_name)
             logging.debug("Generated filename pattern '%s'", self.conf.fn_ptn)
 
-    def on_interlock_change(self, value):
+    def on_interlock_change(self, value: bool) -> None:
         """
         If the connected interlock status changes, the label on the acquisition panel has to
         be updated. Either the status is not triggered and the notification label will not be
         visible or the status is triggered and the user is notified through the label.
         Update the label status through calling update_acquisition_time() without any arguments.
-        :param value (BooleanVA): current interlockTriggered VA value
+        :param value: current interlockTriggered VA value
         """
         if value == self._interlockTriggered:
             # if the value did not change in respect to the previous value
             return
 
-        logging.warning(f"Interlock status changed from {not value} -> "
-                        f"{value}")
+        logging.warning(f"Interlock status changed from {not value} -> {value}")
 
         if value:
-            popup.show_message(wx.GetApp().main_frame,
-                               title="Laser safety",
-                               message=f"Laser was suspended automatically due to interlock trigger.",
-                               timeout=10.0,
-                               level=logging.WARNING)
+            # The laser is connected electronically to the interlock, so nothing to do in software.
+            # For the e-beam (to protect the user from X-rays), we force the blanker on.
+            if self._ebeam_blanker:
+                self._pre_interlock_blanker = self._ebeam_blanker.value
+                self._ebeam_blanker.value = True
+                message = "Laser and e-beam were suspended automatically due to interlock trigger."
+            else:
+                message = "Laser was suspended automatically due to interlock trigger."
         else:
-            popup.show_message(wx.GetApp().main_frame,
-                               title="Laser safety",
-                               message=f"Laser interlock trigger is reset to normal.",
-                               timeout=10.0,
-                               level=logging.WARNING)
+            message = "Laser interlock trigger is reset to normal."
+            # Put back the e-beam blanker to its original state, but only if it is (still) forced
+            # on (otherwise, it's a sign that the user is manually handling it).
+            if self._ebeam_blanker and self._ebeam_blanker.value is True:
+                self._ebeam_blanker.value = self._pre_interlock_blanker
+                if self._pre_interlock_blanker is False:
+                    message += " E-beam blanker disabled."
+                elif self._pre_interlock_blanker is None:  # Automatic mode (= blanker active when not acquiring)
+                    message += " E-beam blanker set back to automatic mode."
+
+        popup.show_message(wx.GetApp().main_frame,
+                           title="Laser safety",
+                           message=message,
+                           timeout=10.0,
+                           level=logging.WARNING)
 
         self._interlockTriggered = value
         self.update_acquisition_time()