add cpu status enum

S7.Net.UnitTest/CommunicationTests/ReadPlcStatus.cs

@@ -48,7 +48,7 @@ async Task Client(int port)
             await conn.OpenAsync();
             var status = await conn.ReadStatusAsync();
 
-            Assert.AreEqual(0x08, status);
+            Assert.AreEqual(CpuStatus.Run, status);
             conn.Close();
         }
 

S7.Net/Enums.cs

@@ -218,4 +218,14 @@ public enum VarType
         /// </summary>
         Time
     }
+
+    /// <summary>
+    /// cpu current status
+    /// </summary>
+    public enum CpuStatus : byte
+    {
+        Unknown = 0x00,
+        Run = 0x08,
+        Stop = 0x04,
+    }
 }

S7.Net/PlcAsynchronous.cs

@@ -347,12 +347,11 @@ public async Task WriteClockAsync(System.DateTime value, CancellationToken cance
         /// <param name="cancellationToken">The token to monitor for cancellation requests. The default value is None.
         /// Please note that cancellation is advisory/cooperative and will not lead to immediate cancellation in all cases.</param>
         /// <returns>A task that represents the asynchronous operation, with it's result set to the current PLC status on completion.</returns>
-        public async Task<byte> ReadStatusAsync(CancellationToken cancellationToken = default)
+        public async Task<CpuStatus> ReadStatusAsync(CancellationToken cancellationToken = default)
         {
             var dataToSend = BuildSzlReadRequestPackage(0x0424, 0);
             var s7data = await RequestTsduAsync(dataToSend, cancellationToken);
-
-            return (byte) (s7data[37] & 0x0f);
+            return (CpuStatus)(s7data[37] & 0x0f);
         }
 
         /// <summary>

S7.Net/PlcSynchronous.cs

@@ -520,12 +520,11 @@ public void WriteClock(System.DateTime value)
         /// Read the current status from the PLC. A value of 0x08 indicates the PLC is in run status, regardless of the PLC type.
         /// </summary>
         /// <returns>The current PLC status.</returns>
-        public byte ReadStatus()
+        public CpuStatus ReadStatus()
         {
             var dataToSend = BuildSzlReadRequestPackage(0x0424, 0);
             var s7data = RequestTsdu(dataToSend);
-
-            return (byte) (s7data[37] & 0x0f);
+            return (CpuStatus)(s7data[37] & 0x0f);
         }
 
         private byte[] RequestTsdu(byte[] requestData) => RequestTsdu(requestData, 0, requestData.Length);