fix(blastware_file): remove harmful "duplicate header+STRT" strip logic to preserve valid waveform data

CHANGELOG.md

@@ -4,6 +4,28 @@ All notable changes to seismo-relay are documented here.
 
 ---
 
+## v0.14.2 — 2026-05-04
+
+### Fixed
+
+- **`blastware_file.py` — removed harmful "duplicate header+STRT" strip.**
+  The v0.13.x strip logic was matching the byte sequence `00 12 03 00 STRT`
+  in legitimate waveform data — sample chunks at counter `0x1000` and
+  beyond often contain those bytes coincidentally — and zeroing 25 bytes
+  of valid samples per match.  This is why event 0 (event-1 case in the
+  protocol) downloads of >1-sec recordings always failed in BW: the strip
+  destroyed real data at body offset `0x1012..0x102B` and propagated
+  alignment differences through the rest of the body.  Sub-1-sec events
+  worked because their `end_offset` was below `0x1002`, so no sample
+  chunks landed in the metadata-page region and the strip's needle never
+  matched.  Verified fix by re-feeding the BW 5-1-26 "copy 3sec" capture's
+  A5 frames into the file builder: output is now byte-identical to BW's
+  saved `M529LKIQ.G10` reference (8708 bytes, 0 differences).
+- BW already concatenates frame contributions in stream order without
+  any de-duplication; SFM now does the same.
+
+---
+
 ## v0.14.1 — 2026-05-04
 
 ### Fixed

CLAUDE.md

@@ -2,7 +2,7 @@
 
 Ground-up Python replacement for **Blastware**, Instantel's Windows-only software for
 managing MiniMate Plus seismographs. Connects over direct RS-232 or cellular modem
-(Sierra Wireless RV50 / RV55). Current version: **v0.14.1**.
+(Sierra Wireless RV50 / RV55). Current version: **v0.14.2**.
 
 When new information about the protocol is discovered, please update the instantel_protocol_reference.md with the findings in addition to this document
 

minimateplus/blastware_file.py

@@ -732,24 +732,18 @@ def write_blastware_file(
         bytes(all_bytes[-28:]).hex() if len(all_bytes) >= 28 else bytes(all_bytes).hex(),
     )
 
-    # Strip embedded "duplicate header+STRT" blocks from body (v0.14.1).
-    # Chunk@0x1000 sometimes lands on the device's metadata-mirror page,
-    # whose response includes a 25-byte "00 12 03 00 STRT ..." block that
-    # mirrors the file's own header + STRT record.  BW treats embedded STRT
-    # markers as second-event starts and rejects the file.  Replace these
-    # blocks with zeros to preserve file size + alignment.
-    needle = b"\x00\x12\x03\x00STRT"
-    pos = bytes(all_bytes).find(needle)
-    while pos >= 0:
-        end = pos + 25
-        if end <= len(all_bytes):
-            all_bytes[pos:end] = b"\x00" * 25
-            log.warning(
-                "write_blastware_file: stripped duplicate header+STRT at "
-                "all_bytes[%d:%d] (replaced with 25 zero-bytes)",
-                pos, end,
-            )
-        pos = bytes(all_bytes).find(needle, end)
+    # NOTE: The "duplicate header+STRT strip" logic from v0.13.x has been
+    # REMOVED in v0.14.2.  Under the v0.14.0 BW-exact 5A walk, body assembly
+    # is just contiguous concatenation of frame contributions in stream order
+    # (probe → meta@0x1002 → meta@0x1004 → samples → TERM), exactly as BW
+    # writes its files.  The previous strip was matching the `00 12 03 00 STRT`
+    # byte sequence in legitimate waveform data — sample chunks at counter
+    # 0x1000 and beyond often contain those bytes coincidentally — and
+    # zeroing 25 bytes of valid samples per match.  Compared to a known-good
+    # BW reference for the same 3-sec event 0, the strip introduced 26 bytes
+    # of zeros that BW did not have, then propagated alignment differences
+    # through the rest of the body.  See decode_test/5-1-26/bw vs SFM diff
+    # at file[0x1012..0x102B] (2026-05-04 analysis).
 
     # Find the first valid 0e 08 footer marker (v0.14.0).
     footer_pos = -1