fix: Workaround for modbus tcp responses w/o address

davidrapan · Dec 9, 2024 · 9c802f3 · 9c802f3
1 parent 2b00be4
commit 9c802f3
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Showing 2 changed files with 4 additions and 1 deletion.
diff --git a/custom_components/solarman/api.py b/custom_components/solarman/api.py
@@ -47,7 +47,7 @@ def __init__(self, address, serial, port, mb_slave_id):
         self._passthrough = False
 
     async def _tcp_send_receive_frame(self, mb_request_frame):
-        return mb_response_adu if not len(mb_response_adu := await self._send_receive_v5_frame(mb_request_frame)) == 10 else mb_response_adu + b'\x00\x01'
+        return mb_response_adu if (l := len(mb_response_adu := await self._send_receive_v5_frame(mb_request_frame))) and not 8 <= l <= 10 else mb_response_adu + b_(b'\x00\x01', 10 - l)
 
     async def _tcp_parse_response_adu(self, mb_request_frame):
         return parse_response_adu(await self._tcp_send_receive_frame(mb_request_frame), mb_request_frame)

diff --git a/custom_components/solarman/common.py b/custom_components/solarman/common.py
@@ -122,6 +122,9 @@ def is_ethernet_frame(frame):
             return int.from_bytes(frame[5:6], byteorder = "big") == len(frame[6:])
     return False
 
+def b_(suffix, count):
+    return b'\x00' * count + suffix
+
 def format_exception(e):
     return re.sub(r"\s+", " ", f"{type(e).__name__}{f': {e}' if f'{e}' else ''}")