From c6ff98c139634c92992dec28d85460747b0f2d05 Mon Sep 17 00:00:00 2001
From: Samuele Locatelli <samuele@steamware.local.net>
Date: Tue, 21 Jul 2020 17:44:43 +0200
Subject: [PATCH] Fix endianness 4 UserSoftKeys

---
 CMS_CORE_Library/S7Net/Nc_S7Net.cs | 11 +++++++++--
 CMS_CORE_Library/Utils/Nc_Utils.cs | 24 ++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/CMS_CORE_Library/S7Net/Nc_S7Net.cs b/CMS_CORE_Library/S7Net/Nc_S7Net.cs
index 8d769d4..ab0c08f 100644
--- a/CMS_CORE_Library/S7Net/Nc_S7Net.cs
+++ b/CMS_CORE_Library/S7Net/Nc_S7Net.cs
@@ -822,8 +822,15 @@ namespace CMS_CORE_Library.S7Net
 
             if (libraryError.IsError())
                 return libraryError;
+
+            // need byte swap!
+            List<int> fixValues = new List<int>();
+            foreach(var item in readValues)
+            {
+                fixValues.Add(SwapBytes(item));
+            }
             // Convert ints into an array of bools
-            bool[] bits = IntToBits(readValues.ToArray());
+            bool[] bits = IntToBits(fixValues.ToArray());
 
             // Convert array into structured data
             for (ushort i = 0; i < bits.Count() / 2; i++)
@@ -845,7 +852,7 @@ namespace CMS_CORE_Library.S7Net
             if (id > USER_SOFTKEYS_NUMBER)
                 return INCORRECT_PARAMETERS_ERROR;
 
-            // Write strobe into memory --> check if bitArray
+            // Write strobe into memory --> false because is bitArray
             CmsError libraryError = PLC_WStrobe(false, USER_SOFT_KEYS_ACK, USER_SOFT_KEYS_CLICKED, id);
             if (libraryError.IsError())
                 return libraryError;
diff --git a/CMS_CORE_Library/Utils/Nc_Utils.cs b/CMS_CORE_Library/Utils/Nc_Utils.cs
index dc56657..3515087 100644
--- a/CMS_CORE_Library/Utils/Nc_Utils.cs
+++ b/CMS_CORE_Library/Utils/Nc_Utils.cs
@@ -171,6 +171,30 @@ namespace CMS_CORE_Library.Utils
         {
             return IntToBits(new int[] { val });
         }
+        /// <summary>
+        /// Swap byte in 32bit DWord (uint/uint)
+        /// </summary>
+        /// <param name="x"></param>
+        /// <returns></returns>
+        internal static uint SwapBytes(uint x)
+        {
+            // swap adjacent 16-bit blocks
+            x = (x >> 16) | (x << 16);
+            // swap adjacent 8-bit blocks
+            return ((x & 0xFF00FF00) >> 8) | ((x & 0x00FF00FF) << 8);
+        }
+        /// <summary>
+        /// Swap byte in 32bit DWord (int/int)
+        /// </summary>
+        /// <param name="x"></param>
+        /// <returns></returns>
+        internal static int SwapBytes(int x)
+        {
+            byte[] bytes = BitConverter.GetBytes(x);
+            Array.Reverse(bytes);
+            int result = BitConverter.ToInt32(bytes, 0);
+            return result;
+        }
 
         // Convert array of integers in an array of bools
         internal static bool[] IntToBits(int[] val)