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Support Questions / Basic help with Allen Bradley UDT
« on: September 01, 2023, 09:53:38 AM »
I have a UDT in a Allen Bradly PLC. I am using version 3.99x. I have tried 'READUDT' but it returns "'ReadUDT' is not a member of 'EthernetIPforCLXCom1'"? I am having issue understanding how to determine where to start each tag and how many bytes to read. All strings are 82 long and the format of the UDT is:
I am using the following to read and display the UDT for testing but some of them come back as gibberish. I am sure it is in my not understanding what bytes belong to each tag. As the control works amazing for reading the tags separately. Can someone help give me a basic understanding of the byte offsets and how to calculate them?
Code: [Select]
Public Class CDS 'Common Data Structure
Public PalletNumber As String
Public ProductionOrderID As String
Public InternalOrderID As String
Public ItemNumber As String
Public ItemName As String
Public LotCode As String
Public ItemGroup As String
Public Barcode As String
Public CasesPerPallet As Int16
Public ProductType As String
Public Quarantine As Boolean
Public QuarantineOrderID As String
Public TimeStamp As String
Public PartialCaseCount As Int16
Public PartialP As Boolean
Public MoverClassification As String
Public ReservedSalesOrderID As String
Public Destination As String
Public Location As String
Public State As String
Public Notes As String
End ClassI am using the following to read and display the UDT for testing but some of them come back as gibberish. I am sure it is in my not understanding what bytes belong to each tag. As the control works amazing for reading the tags separately. Can someone help give me a basic understanding of the byte offsets and how to calculate them?
Code: [Select]
Private Function ReadWO(ByVal tag As String) As String
Dim bytes As Byte() = EthernetIPforCLXCom1.ReadRaw(tag)
Dim CommonData As CDS = New CDS With {
.PalletNumber = ExtractStringField(bytes, 4, 82),
.ProductionOrderID = ExtractStringField(bytes, 90, 82),
.InternalOrderID = ExtractStringField(bytes, 176, 82),
.ItemNumber = ExtractStringField(bytes, 268, 82),
.ItemName = ExtractStringField(bytes, 354, 82),
.LotCode = ExtractStringField(bytes, 440, 82),
.ItemGroup = ExtractStringField(bytes, 529, 82),
.Barcode = ExtractStringField(bytes, 612, 82),
.CasesPerPallet = BitConverter.ToInt16(bytes, 698),
.ProductType = ExtractStringField(bytes, 710, 82),
.Quarantine = BitConverter.ToBoolean(bytes, 744),
.QuarantineOrderID = ExtractStringField(bytes, 746, 82),
.TimeStamp = ExtractStringField(bytes, 890, 82),
.PartialCaseCount = BitConverter.ToInt16(bytes, 976),
.PartialP = BitConverter.ToBoolean(bytes, 912),
.MoverClassification = ExtractStringField(bytes, 914, 82),
.ReservedSalesOrderID = ExtractStringField(bytes, 996, 82),
.Destination = ExtractStringField(bytes, 1078, 82),
.Location = ExtractStringField(bytes, 1160, 82),
.State = ExtractStringField(bytes, 1242, 82),
.Notes = ExtractStringField(bytes, 1324, 82)
}
PrintClassFields(CommonData)
' Dim MyUDT As DateTimeUDT = EthernetIPforCLXCom1.ReadUDT("MyUDT", GetType(DateTimeUDT))
End Function
Private Function ExtractStringField(bytes As Byte(), offset As Integer, length As Integer) As String
Dim fieldBytes(length - 1) As Byte
Array.Copy(bytes, offset, fieldBytes, 0, length)
Return Encoding.Default.GetString(fieldBytes).Trim().Replace(Convert.ToChar(0), "")
End Function
Sub PrintClassFields(obj As Object)
Dim type As Type = obj.GetType()
For Each fieldInfo As FieldInfo In type.GetFields()
Dim fieldName As String = fieldInfo.Name
Dim fieldValue As Object = fieldInfo.GetValue(obj)
Debug.WriteLine(fieldName & " : " & fieldValue)
Next
End Sub