updates to evse

eg4battery/bin/eg4-battery

@@ -292,19 +292,18 @@ def decode_modbus_response(frame: ModbusFrame) -> dict[str, Any]:
 # live probing of a single pack. See ../NOTES.md "Register map" section.
 # High-confidence fields promoted to named entities; unknowns (reg 32, 35,
 # 38-40, 43-45) still emitted as register_NN for correlation.
-
-_WARNING_BITS = [
-    "pack_ov", "cell_ov", "pack_uv", "cell_uv",
-    "charge_oc", "discharge_oc", "temp_anomaly", "mos_ot",
-    "charge_ot", "discharge_ot", "charge_ut", "discharge_ut",
-    "low_capacity", "other_error",
-]
-_PROTECTION_BITS = [
-    "pack_ov", "cell_ov", "pack_uv", "cell_uv",
-    "charge_oc", "discharge_oc", "temp_anomaly", "mos_ot",
-    "charge_ot", "discharge_ot", "charge_ut", "discharge_ut",
-    "float_stopped", "discharge_sc",
-]
+#
+# regs 33 and 34 USED to decode as warning_* / protection_* bitfields here,
+# per the lv_host.app UI display order. That mapping was wrong: live probe
+# (2026-05-09, all 3 packs) showed reg33 == reg34 always, with both halves
+# of each register equal to the byte value of reg20 (temperature_03):
+#     pack 1/2 temp_03 = 19 (0x13)  →  reg33 = reg34 = 0x1313
+#     pack 3   temp_03 = 18 (0x12)  →  reg33 = reg34 = 0x1212
+# i.e. the "alarms that flipped between packs" were just a 1 °C ambient
+# difference, decoded as if the temperature byte were a 14-bit alarm mask.
+# The real alarm word is reg35 (error_code), already exposed and = 0 on
+# healthy packs. Don't re-add reg33/34 as alarms without first confirming
+# they break out of the temp-mirror pattern under a real fault condition.
 
 
 def _signed16(v: int) -> int:
@@ -357,13 +356,10 @@ def decode_eg4_modbus_regs(regs: list[int], expose_raw: bool = False) -> dict[st
     # --- max charge/discharge current limit (reg 31), A ---
     out["max_current_limit"] = round(regs[31] / 100.0, 2)
 
-    # --- bitfields: warnings (reg 33), protections (reg 34), error code (reg 35) ---
-    warn = regs[33]
-    for i, name in enumerate(_WARNING_BITS):
-        out[f"warning_{name}"] = "on" if (warn >> i) & 1 else "off"
-    prot = regs[34]
-    for i, name in enumerate(_PROTECTION_BITS):
-        out[f"protection_{name}"] = "on" if (prot >> i) & 1 else "off"
+    # --- error / alarm word (reg 35) ---
+    # reg 33/34 used to decode as warning_/protection_ bitfields but were
+    # actually mirroring a temperature byte — see the file-header comment.
+    # reg 35 is the canonical alarm word; 0 on healthy packs.
     out["error_code"] = regs[35]
 
     # --- static-ish (regs 36, 37) ---
@@ -706,12 +702,6 @@ _FIELD_META.update({
     "firmware_version":     (None,  None,          None,          "mdi:chip"),
     "firmware_date":        (None,  None,          None,          "mdi:calendar"),
 })
-for _name in _WARNING_BITS:
-    _FIELD_META[f"warning_{_name}"] = (None, None, None, "mdi:alert")
-for _name in _PROTECTION_BITS:
-    _FIELD_META[f"protection_{_name}"] = (None, None, None, "mdi:shield-alert")
-
-
 def field_meta(key: str) -> tuple[str | None, str | None, str | None, str | None]:
     if key.startswith("register_"):
         return (None, None, "measurement", "mdi:numeric")