fix: strip space padding from the structured order code

CHANGES.md

@@ -44,6 +44,9 @@ Unreleased
   block (method `0x12`) that real engineering tools send; both previously used the header of a request without data
   and an 8-byte parameter block (#942).
 
+* `get_order_code` no longer keeps the trailing space padding of the order code on S7-1200/1500 CPUs, for example
+  `6ES7 212-1BE40-0XB0 ` is now `6ES7 212-1BE40-0XB0` (#949).
+
 ### Documentation
 
 * Add a "Tested and Verified Hardware" section to the PLC support matrix, listing the CPUs, firmware versions and

snap7/szl.py

@@ -104,7 +104,7 @@ def _parse_order_code_structured(data: bytes, record_len: int, ndr: int, order_c
 
         if record_id == 0x0001 and record_len >= 22:
             found_structured = True
-            order_code.OrderCode = rec[2:22].rstrip(b"\x00")
+            order_code.OrderCode = rec[2:22].rstrip(b"\x00 ")
             if record_len >= 26 and not has_0x0007 and (rec[23] != 0 or rec[24] != 0):
                 order_code.V1, order_code.V2, order_code.V3 = rec[23], rec[24], rec[25]
 

tests/test_server.py

@@ -857,6 +857,20 @@ def test_parse_order_code_s71516f(self) -> None:
         self.assertEqual(result.V2, 9)
         self.assertEqual(result.V3, 2)
 
+    def test_parse_order_code_strips_trailing_space(self) -> None:
+        """The structured MLFB field is space padded on real PLCs; the padding is not part of the order code."""
+        from snap7.szl import parse_order_code_szl
+        from snap7.type import S7SZL
+
+        payload = b"\x00\x1c\x00\x01\x00\x01" + b"6ES7 212-1BE40-0XB0 " + b"\x00\x00\x00\x02\x00\x00"
+        szl = S7SZL()
+        szl.Header.LengthDR = len(payload)
+        for i, b in enumerate(payload):
+            szl.Data[i] = b
+
+        result = parse_order_code_szl(szl)
+        self.assertEqual(result.OrderCode, b"6ES7 212-1BE40-0XB0")
+
     def test_parse_order_code_s71510sp(self) -> None:
         """Parse a real S7-1510SP dump — should use 0x0007 firmware, not 0x0081 boot loader.