debug: figuring out whats wrong with waveform viewer

minimateplus/client.py

@@ -1395,6 +1395,18 @@ def _decode_a5_waveform(
     total_samples   = struct.unpack_from(">H", strt, 14)[0]
     pretrig_samples = struct.unpack_from(">H", strt, 16)[0]
 
+    # Sanity check: pretrig must be less than total_samples.
+    # If not, the STRT layout is suspect (DLE-stuffing shift, different record variant, etc.).
+    # Log the raw bytes for diagnosis and clamp pretrig to 0 so the viewer renders.
+    if pretrig_samples >= total_samples:
+        log.warning(
+            "_decode_a5_waveform: pretrig_samples=%d >= total_samples=%d — "
+            "STRT layout suspect. Raw strt[0:21]: %s  "
+            "Clamping pretrig to 0 for rendering.",
+            pretrig_samples, total_samples, strt[0:21].hex(' '),
+        )
+        pretrig_samples = 0
+
     # strt[18] is a record-mode/type byte, NOT rectime in seconds.
     # Confirmed from analysis of 4-9-26 ACH capture (15 distinct events):
     #   flags=0xFFFE (single-shot) → strt[18]=0x46 ('F') for all events regardless of duration
@@ -1412,8 +1424,10 @@ def _decode_a5_waveform(
 
     log.debug(
         "_decode_a5_waveform: STRT total_samples=%d pretrig=%d "
-        "strt[18]=0x%02X (mode byte, not seconds) computed_rectime=%ds",
+        "strt[18]=0x%02X (mode byte, not seconds) computed_rectime=%ds  "
+        "raw strt[0:21]: %s",
         total_samples, pretrig_samples, strt[18], rectime_seconds,
+        strt[0:21].hex(' '),
     )
 
     # ── Collect per-frame waveform bytes with global offset tracking ─────────