changed PCAP.SAMPLES to have None in fields

Thus it will use a `uint32` datatype.

src/pandablocks/connections.py

@@ -330,7 +330,14 @@ def _handle_header_body(self):
                 name, capture = SAMPLES_FIELD.rsplit(".", maxsplit=1)
                 fields.insert(
                     0,
-                    FieldCapture(name, np.dtype("uint32"), capture, 1.0, 0.0, ""),
+                    FieldCapture(
+                        name=name,
+                        type=np.dtype("uint32"),
+                        capture=capture,
+                        scale=None,
+                        offset=None,
+                        units=None,
+                    ),
                 )
             self._frame_dtype = np.dtype(
                 [(f"{f.name}.{f.capture}", f.type) for f in fields]

src/pandablocks/hdf.py

@@ -198,7 +198,11 @@ def mean_callable(data):
                 return (data[column_name] * field.scale / gate_duration) + field.offset
 
             return mean_callable
-        elif raw and not field.is_pcap_bits and (field.scale != 1 or field.offset != 0):
+        elif (
+            raw
+            and not field.is_pcap_bits_or_samples
+            and (field.scale != 1 or field.offset != 0)
+        ):
             return lambda data: data[column_name] * field.scale + field.offset
         else:
             return lambda data: data[column_name]

src/pandablocks/responses.py

@@ -244,9 +244,10 @@ class FieldCapture:
 
     @property
     def raw_mode_dataset_dtype(self) -> np.dtype:
-        """We use double for all dtypes, unless the field is a PCAP.BITS."""
+        """We use double for all dtypes,
+        unless the field is a PCAP.BITS or PCAP.SAMPLES."""
 
-        if self.is_pcap_bits:
+        if self.is_pcap_bits_or_samples:
             return self.type
 
         if None in (self.scale, self.offset, self.units):
@@ -257,8 +258,8 @@ def raw_mode_dataset_dtype(self) -> np.dtype:
         return np.dtype("float64")
 
     @property
-    def is_pcap_bits(self) -> bool:
-        """Return True if this field is a PCAP.BITS field"""
+    def is_pcap_bits_or_samples(self) -> bool:
+        """Return True if this field is a PCAP.BITS or PCAP.SAMPLES field"""
         return self.scale is None and self.offset is None and self.units is None
 
 

tests/test_hdf.py

@@ -71,7 +71,7 @@ def test_field_capture_pcap_bits():
         units=None,
     )
 
-    assert pcap_bits_frame_data.is_pcap_bits
+    assert pcap_bits_frame_data.is_pcap_bits_or_samples
     assert pcap_bits_frame_data.raw_mode_dataset_dtype is np.dtype("uint32")
 
     some_other_frame_data = FieldCapture(
@@ -83,7 +83,7 @@ def test_field_capture_pcap_bits():
         units="",
     )
 
-    assert not some_other_frame_data.is_pcap_bits
+    assert not some_other_frame_data.is_pcap_bits_or_samples
     assert some_other_frame_data.raw_mode_dataset_dtype is np.dtype("float64")
 
     malformed_frame_data = FieldCapture(
@@ -95,7 +95,7 @@ def test_field_capture_pcap_bits():
         units="",
     )
 
-    assert not some_other_frame_data.is_pcap_bits
+    assert not some_other_frame_data.is_pcap_bits_or_samples
     with pytest.raises(
         ValueError,
         match="If any of `scale`, `offset`, or `units` is set, all must be set",