Updates

csv_preprocessor.py

@@ -65,9 +65,6 @@ CLK_LP_LOW_MIN_NS = 300.0
 HS_BURST_AMPLITUDE_MIN_MV = 40.0  # mV — below this, no real HS burst is present
 #   Lowered from 50 mV: 48 mV capture (0001) was a false alarm; true flicker (0008) at 34 mV.
 
-HS_BURST_AMPLITUDE_HIGH_MV = 70.0  # mV — above this with short LP-low → anomalous LP states
-#   Normal HS (dynamic video) = ~15–40 mV P95-P5/2 on LP probe (RC-filtered).
-#   LP-01/LP-10 states in the burst window (cap 0042 type) produce 130+ mV → flag these.
 
 # Mode A minimum amplitude: LP-11-return edge artifacts produce near-zero amplitude in the
 # burst window (burst is pure LP-low DC between two LP-11 regions).  Require ≥ this to
@@ -997,7 +994,7 @@ def analyze_lp_file(path: Path) -> "LPMetrics":
                 f"(TCLK_PREPARE+TCLK_ZERO minimum) — SN65DSI83 may fail to lock CLK lane"
             )
 
-    # Flicker suspect: four confirmed failure modes on this hardware:
+    # Flicker suspect: three confirmed failure modes on this hardware:
     #
     #   A) Normal LP-low (~342–380 ns) → bridge misses SoT → returns to LP-11
     #      Signature: lp11_to_hs fires at real LP-low end (~347 ns), hs_amplitude ≈ 15–30 mV.
@@ -1007,21 +1004,13 @@ def analyze_lp_file(path: Path) -> "LPMetrics":
     #   A2) LP-11 present, HS attempt made but amplitude too weak for rolling-std to fire
     #      Signature: lp11_to_hs is None (rolling-std < HS_OSC_STD_V throughout 500 ns
     #      lookahead), hs_amplitude < 50 mV, LP-11 returns ~500 ns later.
-    #      Root cause: marginal VDD_DSI (LP-11 sags to ~1.0 V vs 1.2 V nominal), reducing
-    #      HS drive strength below the detection threshold.
-    #      Confirmed: capture 0010 (lp11_to_hs=None, amp≈32 mV, LP-11 returned at +513 ns).
     #
-    #   B) Short LP-low (50–200 ns, vs nominal ~342–380 ns) → marginal SoT timing
+    #   B) Short LP-low (< 200 ns, vs nominal ~342–380 ns) → anomalous SoT timing.
-    #      → HS burst starts but is weak, hs_amplitude ≈ 40–60 mV (vs normal 100–122 mV).
+    #      Flag on LP-low duration alone: any lp_low < 200 ns is outside the normal range
-    #      Signature: lp_low anomalously short, lp11_to_hs fires at noise spike (~3 ns).
+    #      and warrants investigation regardless of amplitude or rolling-std state.
-    #      The lp11_to_hs guard cannot be used here, so LP-low duration gates the check.
+    #      Confirmed: capture 0124 (lp_low=108 ns).
-    #      Confirmed example: capture 0120 (lp_low=108 ns, lp11_to_hs=1.7 ns, amp=49 mV).
     #
-    #   C) No LP-11 detected at all → MIPI link silent or stuck
+    #   C) No LP-11 detected at all → MIPI link silent or stuck.
-    #      Signature: no LP-11 region found, lp_transition_valid=False, no LP or HS seen.
-    #      This is the most severe failure: the bridge or DSI IP has stopped outputting.
-    #      Confirmed: follow-up of capture 13 (no LP-11, no HS) while display was flickering.
-    #      Guard: only flag DAT lane (not CLK which is normally in continuous HS mode).
     #
     # Only flag DAT lane (CLK is continuous HS — LP states not expected).
     _lp_low_short = (
@@ -1047,26 +1036,9 @@ def analyze_lp_file(path: Path) -> "LPMetrics":
             # weak oscillations are misclassified as LP-low, masking the true HS failure
             or lp11_to_hs_ns is None
             # Mode B: LP-low anomalously short + low amplitude = marginal HS launch.
-            # Gated by hs_rolling_std_found: if HS actually launched (rolling-std fires
+            or _lp_low_short
-            # after LP-low ends), LP-low being short is a timing anomaly but not a flicker.
-            or (_lp_low_short and not hs_rolling_std_found)
-            # Mode D: LP-low normal, noise-spike lp11_to_hs (< 50 ns), low HS amplitude.
-            # Requires video/dynamic content. Gate: if rolling-std fires after LP-low ends,
-            # HS launched normally and the early lp11_to_hs was just the LP-low edge trigger.
-            or (lp11_to_hs_ns is not None
-                and lp11_to_hs_ns < LP_LOW_DUR_MIN_NS
-                and not _lp_low_short
-                and not hs_rolling_std_found)
         )
     )
-    # Mode E: short LP-low with anomalously HIGH amplitude — LP-01/LP-10 states in the
-    # burst window (link failed to launch HS cleanly).  Normal LP probe HS = 15–40 mV;
-    # LP-01/LP-10 DC levels produce 70+ mV.  Confirmed: cap 0042 (lp_low=61 ns, amp=133 mV).
-    hs_burst_anomalous = (
-        _lp_low_short
-        and hs_amplitude_mv is not None
-        and hs_amplitude_mv > HS_BURST_AMPLITUDE_HIGH_MV
-    )
     # Mode C: no LP-11 at all → link silent (but exclude CLK which is always HS)
     link_silent = (
         channel == "dat"
@@ -1080,13 +1052,9 @@ def analyze_lp_file(path: Path) -> "LPMetrics":
             or (
                 lp_transition_valid
                 and (
-                    # LP-00 absent entirely (LP-01/LP-00 skipped — SoT never completed).
-                    # Short-but-non-zero LP-low is handled by Mode B inside hs_burst_absent;
-                    # flagging it standalone (even with healthy HS amplitude) caused false
-                    # positives when noise triggers gave lp_low < 50 ns with normal HS.
                     lp_low_duration_ns is None
                     or hs_burst_absent
-                    or hs_burst_anomalous
+                    or _lp_low_short
                 )
             )
         )
@@ -1108,6 +1076,7 @@ def analyze_lp_file(path: Path) -> "LPMetrics":
         hs_amplitude_mv      = hs_amplitude_mv,
         lp_transition_valid  = lp_transition_valid,
         clk_lp_startup_ok    = clk_lp_startup_ok,
+        hs_rolling_std_found = hs_rolling_std_found,
         flicker_suspect      = flicker_suspect,
         warnings             = warnings,
     )