From 4149424ed08a10da160ba7a40a4d6acb35a9be4c Mon Sep 17 00:00:00 2001
From: Artur Glavic <artur.glavic@psi.ch>
Date: Tue, 19 May 2026 09:43:32 +0200
Subject: [PATCH] Implement monitor da00 format as fallback timing reference

---
 eos/event_data_types.py |  5 +++++
 eos/file_reader.py      | 16 ++++++++--------
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/eos/event_data_types.py b/eos/event_data_types.py
index 2ccfbf6..d480ba8 100644
--- a/eos/event_data_types.py
+++ b/eos/event_data_types.py
@@ -29,6 +29,11 @@ class AmorTiming:
     chopperPhase: float
     tau: float
 
+@dataclass
+class DA00EventBuffer:
+    signal: np.ndarray
+    time: np.ndarray
+
 # Structured datatypes used for event streams
 EVENT_TYPE = np.dtype([('tof', np.float64), ('pixelID', np.uint32), ('mask', np.int32)])
 PACKET_TYPE = np.dtype([('start_index', np.uint32), ('time', np.int64)])
diff --git a/eos/file_reader.py b/eos/file_reader.py
index d8e37c9..ad30f68 100644
--- a/eos/file_reader.py
+++ b/eos/file_reader.py
@@ -7,7 +7,6 @@ import sys
 import h5py
 import numpy as np
 import logging
-import subprocess
 
 from datetime import datetime
 
@@ -17,7 +16,7 @@ from orsopy.fileio.model_language import SampleModel
 from . import const, compat
 from .header import Header
 from .event_data_types import AmorGeometry, AmorTiming, AmorEventStream, LOG_TYPE, PACKET_TYPE, EVENT_TYPE, PULSE_TYPE, \
-    PC_TYPE
+    PC_TYPE, DA00EventBuffer
 
 try:
     import zoneinfo
@@ -75,7 +74,7 @@ class AmorHeader:
 
             data=('entry1/detector/data', None),  # data group used to load events from
             trigger=('entry1/detector/trigger', float),
-            monitor=('entry1/detector/monitor', float),
+            monitor=('entry1/beam_monitor', None), # special data group (da00 flat-buffer scheme)
             proton_current=('entry1/detector/proton_current', float),
             acquisition_filter=('entry1/detector/acquisition_filter', int),
             )
@@ -147,6 +146,9 @@ class AmorHeader:
                     return output, unit
                 else:
                     return output
+            elif hdfgrp.attrs.get('writer_module', None) == 'da00':
+                # da00 float-buffer stream data
+                return DA00EventBuffer(signal=hdfgrp['signal'][:], time=hdfgrp['time'][:])
             elif dtype is str:
                 return self.read_string(hdf_path)
             else:
@@ -455,11 +457,11 @@ class AmorEventData(AmorHeader):
         events.pixelID = data_group['event_id'][self.first_index:self.last_index+1]
         events.mask = 0
 
+        self._monitor = self.rv('monitor', default=None)
         pulses = self.read_chopper_trigger_stream(packets)
         current = self.read_proton_current_stream(packets)
 
         # read parameter logs not present in old files to ensure they are in self._log_keys if they exist
-        _monitor = self.rv('monitor', default=None)
         _acquisition_filter = self.rv('acquisition_filter', default=None)
 
         self.data = AmorEventStream(events, packets, pulses, current)
@@ -519,10 +521,8 @@ class AmorEventData(AmorHeader):
             pulseTimeS = chopper1TriggerTime
         else:
             logging.critical('     No chopper trigger data available, using event steram instead, pulse filtering will fail!')
-            data_group = self.hdf[self.hdf_paths['data'][0]]
-            startTime = np.array(data_group['event_time_zero'][0], dtype=np.int64)
-            stopTime = np.array(data_group['event_time_zero'][-2], dtype=np.int64)
-            pulseTimeS = np.arange(startTime, stopTime, self.timing.tau*1e9, dtype=np.int64)
+            startTime = np.array(self._monitor.time[0], dtype=np.int64)
+            pulseTimeS = self._monitor.time
         pulses = np.recarray(pulseTimeS.shape, dtype=PULSE_TYPE)
         pulses.time = pulseTimeS
         pulses.monitor = 1. # default is monitor pulses as it requires no calculation