Example #1
0
        public static int CreateRequest(ByteArray message, DataItem[] dataItems)
        {
            message.Add(Header.Template);

            message[Header.Offsets.ParameterCount] = (byte)dataItems.Length;
            var paramSize = dataItems.Length * Parameter.Template.Length;

            Serialization.SetWordAt(message, Header.Offsets.ParameterSize,
                                    (ushort)(2 + paramSize));

            var paramOffset = Header.Template.Length;
            var data        = new ByteArray();

            var itemCount = 0;

            foreach (var item in dataItems)
            {
                itemCount++;
                message.Add(Parameter.Template);
                var value   = Serialization.SerializeDataItem(item);
                var wordLen = item.Value is bool? 1 : 2;

                message[paramOffset + Parameter.Offsets.WordLength] = (byte)wordLen;
                Serialization.SetWordAt(message, paramOffset + Parameter.Offsets.Amount, (ushort)value.Length);
                Serialization.SetWordAt(message, paramOffset + Parameter.Offsets.DbNumber, (ushort)item.DB);
                message[paramOffset + Parameter.Offsets.Area] = (byte)item.DataType;

                data.Add(0x00);
                if (item.Value is bool b)
                {
                    if (item.BitAdr > 7)
                    {
                        throw new ArgumentException(
                                  $"Cannot read bit with invalid {nameof(item.BitAdr)} '{item.BitAdr}'.", nameof(dataItems));
                    }

                    Serialization.SetAddressAt(message, paramOffset + Parameter.Offsets.Address, item.StartByteAdr,
                                               item.BitAdr);

                    data.Add(0x03);
                    data.AddWord(1);

                    data.Add(b ? (byte)1 : (byte)0);
                    if (itemCount != dataItems.Length)
                    {
                        data.Add(0);
                    }
                }
                else
                {
                    Serialization.SetAddressAt(message, paramOffset + Parameter.Offsets.Address, item.StartByteAdr, 0);

                    var len = value.Length;
                    data.Add(0x04);
                    data.AddWord((ushort)(len << 3));
                    data.Add(value);

                    if ((len & 0b1) == 1 && itemCount != dataItems.Length)
                    {
                        data.Add(0);
                    }
                }

                paramOffset += Parameter.Template.Length;
            }

            message.Add(data.Array);

            Serialization.SetWordAt(message, Header.Offsets.MessageLength, (ushort)message.Length);
            Serialization.SetWordAt(message, Header.Offsets.DataLength, (ushort)(message.Length - paramOffset));

            return(message.Length);
        }