Updating to be more clear about how AI_start_delay is calculated,

particularly in the case of devices that use AI_start_delay_ticks.

Author: dihm

labscript_devices/NI_DAQmx/blacs_workers.py

@@ -537,7 +537,7 @@ def transition_to_buffered(self, device_name, h5file, initial_values, fresh):
         self.h5_file = h5file
         self.buffered_rate = device_properties['acquisition_rate']
         if device_properties['start_delay_ticks']:
-            # delay is defined in sample clock ticks
+            # delay is defined in sample clock ticks, calculate in sec and save for later
             self.AI_start_delay = self.AI_start_delay_ticks*self.buffered_rate
         self.acquired_data = []
         # Stop the manual mode task and start the buffered mode task:

labscript_devices/NI_DAQmx/labscript_devices.py

@@ -97,7 +97,7 @@ def __init__(
         AI_range=None,
         AI_range_Diff=None,
         AI_start_delay=0,
-        AI_start_delay_ticks=0,
+        AI_start_delay_ticks=None,
         AI_term='RSE',
         AI_term_cfg=None,
         AO_range=None,
@@ -231,8 +231,14 @@ def __init__(
             raise LabscriptError(dedent(msg.format(AI_term)))
         if AI_term == 'Diff':
             self.AI_range = AI_range_Diff
-        # define AI_start_delay in ticks, assumes AI_start_delay_ticks is defined
-        self.start_delay_ticks = (AI_start_delay != None)
+        if AI_start_delay is None:
+             if AI_start_delay_ticks is not None:
+                # Tell blacs_worker to use AI_start_delay_ticks to define delay
+                self.start_delay_ticks = True
+            else:
+                self.start_delay_ticks = False
+        else:
+            raise LabscriptError("You have specified `AI_start_delay = None` but have not provided `AI_start_delay_ticks`.")
         self.num_AO = num_AO
         self.num_CI = num_CI
         self.ports = ports if ports is not None else {}