Potential fix for pull request finding

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>

Author: georgevigelette

src/openlifu/io/LIFUDFU.py

@@ -13,8 +13,10 @@
 import logging
 import struct
 import time
-from typing import TYPE_CHECKING, Callable
 import unittest
+from typing import TYPE_CHECKING, Callable
+
+import pytest
 
 from openlifu.io.LIFUConfig import OW_ERROR, OW_I2C_PASSTHRU
 
@@ -230,10 +232,10 @@ def test_parse_signed_package_valid(self) -> None:
 
         parsed = parse_signed_package(pkg)
 
-        self.assertEqual(parsed["fw_address"], fw_addr)
-        self.assertEqual(parsed["meta_address"], meta_addr)
-        self.assertEqual(parsed["fw"], fw)
-        self.assertEqual(parsed["meta"], meta)
+        assert parsed["fw_address"] == fw_addr
+        assert parsed["meta_address"] == meta_addr
+        assert parsed["fw"] == fw
+        assert parsed["meta"] == meta
 
     def test_parse_signed_package_header_crc_mismatch(self) -> None:
         """Corrupt the header so header CRC verification fails."""
@@ -248,7 +250,7 @@ def test_parse_signed_package_header_crc_mismatch(self) -> None:
         pkg_bytes[4] ^= 0x01
         corrupted = bytes(pkg_bytes)
 
-        with self.assertRaises(ValueError):
+        with pytest.raises(ValueError, match="header CRC mismatch"):
             parse_signed_package(corrupted)
 
     def test_parse_signed_package_payload_crc_mismatch(self) -> None:
@@ -265,7 +267,7 @@ def test_parse_signed_package_payload_crc_mismatch(self) -> None:
         pkg_bytes[hdr_size] ^= 0x01
         corrupted = bytes(pkg_bytes)
 
-        with self.assertRaises(ValueError):
+        with pytest.raises(ValueError, match="payload CRC mismatch"):
             parse_signed_package(corrupted)
 
 
@@ -531,7 +533,6 @@ def __init__(self, uart: LIFUUart,
                  write_read_delay_s: float = 0.005):
         self._uart = uart
         self._addr = i2c_addr
-        self._wr_delay = write_read_delay_s
 
     # --- low-level transport primitives ---
 
@@ -554,11 +555,14 @@ def _write(self, payload: bytes) -> None:
 
     def _exchange(self, payload: bytes, read_len: int,
                   pre_read_delay_s: float | None = None) -> bytes:
-        """Write *payload* to the I2C slave, wait, then read *read_len* bytes back.
-
-        The firmware inserts a fixed 5 ms gap between write and read.
-        An optional extra host-side delay can be added via *pre_read_delay_s*
-        (not usually needed).
+        """Write *payload* to the I2C slave and read *read_len* bytes back.
+
+        The firmware executes a combined write+read transaction and inserts a
+        fixed 5 ms gap between the write and read phases internally.
+        The optional *pre_read_delay_s* parameter adds an extra host-side delay
+        **before** issuing the passthrough transaction (i.e. before the
+        firmware performs the write+read). This does *not* change the internal
+        5 ms gap handled by the firmware and is rarely needed.
         """
         if pre_read_delay_s and pre_read_delay_s > 0:
             time.sleep(pre_read_delay_s)

src/openlifu/io/LIFUTXDevice.py

@@ -5,7 +5,7 @@
 import re
 import struct
 from dataclasses import dataclass, field
-from typing import TYPE_CHECKING, Annotated, Dict, List, Literal, Optional
+from typing import TYPE_CHECKING, Annotated, Dict, List, Literal
 
 import numpy as np
 
@@ -397,7 +397,7 @@ def get_hardware_id(self, module:int=0) -> str:
             logger.error("Unexpected error during process: %s", e)
             raise  # Re-raise the exception for the caller to handle
 
-    def read_config(self, module:int=0) -> Optional[LifuUserConfig]:
+    def read_config(self, module:int=0) -> LifuUserConfig | None:
         """
         Read the user configuration from device flash.
 
@@ -450,7 +450,7 @@ def read_config(self, module:int=0) -> Optional[LifuUserConfig]:
             logger.exception("Unexpected error reading config")
             raise
 
-    def write_config(self, config: LifuUserConfig, module:int=0) -> Optional[LifuUserConfig]:
+    def write_config(self, config: LifuUserConfig, module:int=0) -> LifuUserConfig | None:
         """
         Write user configuration to device flash.
 
@@ -517,7 +517,7 @@ def write_config(self, config: LifuUserConfig, module:int=0) -> Optional[LifuUse
             logger.exception("Unexpected error writing config")
             raise
 
-    def write_config_json(self, json_str: str, module:int=0) -> Optional[LifuUserConfig]:
+    def write_config_json(self, json_str: str, module:int=0) -> LifuUserConfig | None:
         """
         Write user configuration from a JSON string.
 
@@ -540,6 +540,13 @@ def write_config_json(self, json_str: str, module:int=0) -> Optional[LifuUserCon
             return self.write_config(module=module, config=config)
         except json.JSONDecodeError as e:
             logger.error(f"Invalid JSON: {e}")
+            raise ValueError(f"Invalid JSON: {e}") from e
+        except ValueError as v:
+            logger.error("ValueError: %s", v)
+            raise
+        except (OSError, RuntimeError, AttributeError) as e:
+            logger.exception("Unexpected error writing config from JSON")
+            raise
 
     def get_temperature(self, module:int=1) -> float:
         """
@@ -982,7 +989,7 @@ def async_mode(self, enable: bool | None = None) -> bool:
             else:
                 payload = None
 
-            r = self.uart.send_packet(id=None, packetType=OW_CONTROLLER, command=OW_CMD_ASYNC, addr=0, data=payload)
+            r = self.uart.send_packet(id=None, packetType=OW_CMD, command=OW_CMD_ASYNC, addr=0, data=payload)
             self.uart.clear_buffer()
             # r.print_packet()
             if r.packet_type == OW_ERROR:
@@ -1332,7 +1339,7 @@ def write_block(self, identifier: int, start_address: int, reg_values: List[int]
             logger.error("Unexpected error in write_block: %s", e)
             raise  # Re-raise the exception for the caller to handle
 
-    def read_block(self, identifier: int, start_address: int, count: int) -> Optional[List[int]]:
+    def read_block(self, identifier: int, start_address: int, count: int) -> List[int] | None:
         """
         Read a block of consecutive register values from the TX device.
 

src/openlifu/io/LIFUUserConfig.py

@@ -3,14 +3,15 @@
 import json
 import logging
 import struct
+import zlib
 from dataclasses import dataclass
 from typing import Any, Dict
 
 logger = logging.getLogger(__name__)
 
 # Constants from C code
 LIFU_MAGIC = 0x4C494655  # 'LIFU'
-LIFU_VER = 0x00010002    # v1.0.0
+LIFU_VER = 0x00010002    # v1.0.2
 
 @dataclass
 class LifuUserConfigHeader:
@@ -139,6 +140,9 @@ def to_wire_bytes(self) -> bytes:
         # Update header with JSON length
         self.header.json_len = len(json_bytes)
 
+        # Update header CRC based on JSON payload (16-bit from CRC32)
+        self.header.crc = zlib.crc32(json_bytes) & 0xFFFF
+
         # Build wire format
         return self.header.to_bytes() + json_bytes