diff --git a/Sharp7.Rx/Sharp7Connector.cs b/Sharp7.Rx/Sharp7Connector.cs
index 83d9bac..440fb09 100644
--- a/Sharp7.Rx/Sharp7Connector.cs
+++ b/Sharp7.Rx/Sharp7Connector.cs
@@ -168,11 +168,11 @@ internal class Sharp7Connector: IDisposable
         EnsureSuccessOrThrow(result, $"Error writing {operand}{dbNo}:{startByteAddress} bit {bitAdress}");
     }
 
-    public async Task WriteBytes(Operand operand, ushort startByteAddress, byte[] data, ushort dbNo, CancellationToken token)
+    public async Task WriteBytes(Operand operand, ushort startByteAddress, byte[] data, ushort dbNo, ushort bytesToWrite, CancellationToken token)
     {
         EnsureConnectionValid();
 
-        var result = await Task.Factory.StartNew(() => sharp7.WriteArea(operand.ToArea(), dbNo, startByteAddress, data.Length, S7WordLength.Byte, data), token, TaskCreationOptions.None, scheduler);
+        var result = await Task.Factory.StartNew(() => sharp7.WriteArea(operand.ToArea(), dbNo, startByteAddress, bytesToWrite, S7WordLength.Byte, data), token, TaskCreationOptions.None, scheduler);
         token.ThrowIfCancellationRequested();
 
         EnsureSuccessOrThrow(result, $"Error writing {operand}{dbNo}:{startByteAddress}.{data.Length}");
diff --git a/Sharp7.Rx/Sharp7Plc.cs b/Sharp7.Rx/Sharp7Plc.cs
index 3f0b839..bc98040 100644
--- a/Sharp7.Rx/Sharp7Plc.cs
+++ b/Sharp7.Rx/Sharp7Plc.cs
@@ -188,7 +188,7 @@ public class Sharp7Plc : IPlc
             {
                 ValueConverter.WriteToBuffer(buffer, value, address);
 
-                await s7Connector.WriteBytes(address.Operand, address.Start, buffer, address.DbNo, token);
+                await s7Connector.WriteBytes(address.Operand, address.Start, buffer, address.DbNo, address.BufferLength, token);
             }
             finally
             {
@@ -295,7 +295,7 @@ public class Sharp7Plc : IPlc
         StartNotificationLoop();
     }
 
-    private async Task<Unit> GetAllValues(IS7Connector connector)
+    private async Task<Unit> GetAllValues(Sharp7Connector connector)
     {
         if (multiVariableSubscriptions.ExistingKeys.IsEmpty())
             return Unit.Default;