Use prepare_exposures() helper when preparing the ophyd-async detectors.

Author: canismarko

src/haven/devices/detectors/_lambda.py

@@ -14,10 +14,10 @@
 from ophyd_async.epics.adcore import (
     ADArmLogic,
     ADBaseIO,
-    ADImageMode,
     ADWriterType,
     AreaDetector,
     NDPluginBaseIO,
+    prepare_exposures,
 )
 from ophyd_async.epics.core import epics_signal_rw, epics_signal_rw_rbv
 
@@ -65,20 +65,14 @@ class LambdaTriggerLogic(DetectorTriggerLogic):
     driver: ADBaseIO
 
     def get_deadtime(self, exposure: float | None) -> float:
-        # From manual: No readout time in 12-bit, 6-bit and1-bit mode,
+        # From manual: No readout time in 12-bit, 6-bit and 1-bit mode,
         # 1 ms in 24-bit mode
         return 1e-3
 
-    async def prepare_common(self, num: int) -> None:
-        await asyncio.gather(
-            self.driver.num_images.set(num),
-            self.driver.image_mode.set(ADImageMode.MULTIPLE),
-        )
-
     async def prepare_level(self, num: int) -> None:
         task = asyncio.ensure_future(
             asyncio.gather(
-                self.prepare_common(num=num),
+                prepare_exposures(self.driver, num),
                 self.driver.trigger_mode.set(LambdaTriggerMode.EXTERNAL_SEQUENCE),
             )
         )
@@ -88,16 +82,10 @@ async def prepare_level(self, num: int) -> None:
     async def prepare_internal(
         self, num: int, livetime: float, deadtime: float
     ) -> None:
-        task = asyncio.ensure_future(
-            asyncio.gather(
-                self.prepare_common(num=num),
-                self.driver.trigger_mode.set(LambdaTriggerMode.INTERNAL),
-                self.driver.acquire_time.set(livetime),
-                self.driver.acquire_period.set(livetime + deadtime),
-            )
+        await asyncio.gather(
+            self.driver.trigger_mode.set(LambdaTriggerMode.INTERNAL),
+            prepare_exposures(self.driver, num, livetime, deadtime),
         )
-        await self._wait_for_num_images(num)
-        await task
 
     async def _wait_for_num_images(self, num: int):
         """Make sure the number of frames is set properly (not too high)"""

src/haven/devices/detectors/eiger.py

@@ -1,9 +1,15 @@
+import asyncio
 from collections.abc import Sequence
 from dataclasses import dataclass
 
 from ophyd_async.core import DetectorTriggerLogic, PathProvider, SignalR
 from ophyd_async.epics import adcore
-from ophyd_async.epics.adcore import ADBaseIO, ADWriterType, AreaDetector
+from ophyd_async.epics.adcore import (
+    ADBaseIO,
+    ADWriterType,
+    AreaDetector,
+    prepare_exposures,
+)
 
 # from ophyd_async.epics.adcore._utils import ADBaseDataType, convert_ad_dtype_to_np
 from ophyd_async.epics.core import epics_signal_r, epics_signal_rw_rbv
@@ -36,6 +42,13 @@ def get_deadtime(self, exposure: float | None) -> float:
         # keV threshold energy. Set it to 10× to be safe.
         return 3e-5
 
+    async def prepare_internal(
+        self, num: int, livetime: float, deadtime: float
+    ) -> None:
+        await asyncio.gather(
+            prepare_exposures(self.driver, num, livetime, deadtime),
+        )
+
 
 class EigerDetector(AreaDetector):
     """An Eiger area detector, e.g. Eiger 500K."""

src/haven/devices/detectors/xspress.py

@@ -23,7 +23,6 @@
 
 import numpy as np
 from ophyd_async.core import (
-    DEFAULT_TIMEOUT,
     Array1D,
     AsyncStatus,
     DetectorTrigger,
@@ -35,20 +34,19 @@
     StrictEnum,
     TriggerInfo,
     derived_signal_r,
-    observe_value,
     soft_signal_r_and_setter,
 )
 from ophyd_async.epics.adcore import (
     ADArmLogic,
     ADBaseDataType,
     ADBaseIO,
-    ADImageMode,
     ADWriterType,
     AreaDetector,
     NDAttributeDataType,
     NDAttributeParam,
     NDPluginBaseIO,
     ndattributes_to_xml,
+    prepare_exposures,
 )
 from ophyd_async.epics.core import epics_signal_r, epics_signal_rw, epics_signal_x
 
@@ -102,43 +100,23 @@ def get_deadtime(self, exposure: float) -> float:
         return 1e-6
 
     async def prepare_common(self, num: int):
-        await asyncio.gather(
-            self.driver.num_images.set(num),
-            self.driver.image_mode.set(ADImageMode.MULTIPLE),
-            # Hardware deadtime correction is not reliable
-            # https://github.com/epics-modules/xspress3/issues/57
-            self.driver.deadtime_correction.set(False),
-        )
+        # Hardware deadtime correction is not reliable
+        # https://github.com/epics-modules/xspress3/issues/57
+        await self.driver.deadtime_correction.set(False)
 
     async def prepare_internal(self, num: int, livetime: float, deadtime: float):
-        task = asyncio.ensure_future(
-            asyncio.gather(
-                self.prepare_common(num),
-                self.driver.trigger_mode.set(XspressTriggerMode.INTERNAL),
-            )
+        await asyncio.gather(
+            self.prepare_common(num),
+            prepare_exposures(self.driver, num, livetime, deadtime),
+            self.driver.trigger_mode.set(XspressTriggerMode.INTERNAL),
         )
-        # Make sure the number of frames is set properly (not too high)
-        async for num_images in observe_value(
-            self.driver.num_images, done_timeout=DEFAULT_TIMEOUT
-        ):
-            if num_images == num:
-                break
-        await task
 
     async def prepare_level(self, num: int):
-        task = asyncio.ensure_future(
-            asyncio.gather(
-                self.prepare_common(num),
-                self.driver.trigger_mode.set(XspressTriggerMode.TTL_VETO_ONLY),
-            )
+        await asyncio.gather(
+            self.prepare_common(num),
+            prepare_exposures(self.driver, num),
+            self.driver.trigger_mode.set(XspressTriggerMode.TTL_VETO_ONLY),
         )
-        # Make sure the number of frames is set properly (not too high)
-        async for num_images in observe_value(
-            self.driver.num_images, done_timeout=DEFAULT_TIMEOUT
-        ):
-            if num_images == num:
-                break
-        await task
 
 
 class XspressElement(Device):