Below is the original post:
I've inherited tests from someone who is no longer with my company. We're using v 5.35.442.1 to connect to a variety of PLCs.
Everything works fine except for a Siemens S7-200. We're using TOP Server v 5.20.396.0.
When the code tries to write, an exception is thrown:
Caught Exception=OpcLabs.EasyOpc.OperationModel.OpcException: An OPC operation failure with error code -2147467259 (0x80004005) occurred, originating from 'OpcLabs.EasyOpcRaw.DataAccess.RawEasyDAClient'.
The inner exception contains details about the problem.
---> System.Runtime.InteropServices.COMException: Unspecified error
--- End of inner exception stack trace --- at OpcLabs.EasyOpc.DataAccess.IEasyDAClientExtension.WriteItemValue(IEasyDAClient easyDAClient, ServerDescriptor serverDescriptor, DAItemDescriptor itemDescriptor, Object value) at TopSrvrTest.Program.SendReset(String opcServer, String resetAddress) in C:\Users\dlaw\Documents\Visual Studio 2015 \Projects\TopSrvrTest\Program.cs:line 20
When attempting to read, no exception is thrown, but the DAVtq variable's HasValue property is always null.
I have a small program that reproduces the issue (and also shows successful reads and writes for a MicroLogix 1400B), but if I attach it, I can't post to the forum.
The code is very simple, however. For writes:
EasyDAClient dac = new EasyDAClient();
dac.WriteItemValue("SWToolbox.TOPServer.V5", ISOTCP.S7_200_58.RESET", true);
For reads:
dac.ReadItem("SWToolbox.TOPServer.V5", "ISOTCP.S7_200_58.VW1920, DAReadParameter.DeviceSource);