Bacnet BBMD Read request fail

[gowtham31]

I am facing issue while connecting and reading Bacnet device objects through BBMD configuration. Though i get response of complex-Ack i am not able to read any object values. Please check the code below what i have used to read the bacnet object and wireshark packet details.

public void ReadBacnetObject()
{
    IList<BacnetValue> Value;
    BacnetIpUdpProtocolTransport bacnetIpUdpProtocolTransport = new BacnetIpUdpProtocolTransport(0xBAC0, true);
    bacnetIpUdpProtocolTransport.Start();
    bacnetIpUdpProtocolTransport.Bvlc.AddBBMDPeer(new IPEndPoint(IPAddress.Parse("10.155.60.3"), 47808), IPAddress.Parse("255.255.255.255"));
    bacnet_client = new BacnetClient(bacnetIpUdpProtocolTransport);
    bacnet_client.OnIam += new BacnetClient.IamHandler(handler_OnIam);
    //bacnet_client.RegisterAsForeignDevice("10.155.60.3", 30);
    //bacnet_client.RemoteWhoIs("10.155.60.3");
    //Thread.Sleep(20);
    if (bacnet_client.ReadPropertyRequest(new BacnetAddress(BacnetAddressTypes.IP, "10.155.60.23:47808"),  new BacnetObjectId(BacnetObjectTypes.OBJECT_DEVICE, 2000001), BacnetPropertyIds.PROP_OBJECT_LIST, out Value) == false)
    {
        foreach (var item in Value)
        {
            Console.WriteLine($"Able to read data  {item.Tag} + {item.Value} ");
        }
    }
}

Kindly request check if anything went wrong?

[gralin]

@gowtham31 for sure this line is incorrect:

if (bacnet_client.ReadPropertyRequest(..., out Value) == false)

just remove == false. Does this help? If not, does the answer in wireshark dump contain the object list?

[gowtham31]

Thanks Gralin for your response. Removing false check in ReadPropertyRequest doen't help. However i am getting the object list in the wireshark packet as per the below attachment Also from debugging the library, i have noticed that events subscribed in BacnetAsyncResult from BeginReadPropertyRequest such as OnComplexAck are not triggered to complete the EndReadPropertyRequest .

public bool ReadPropertyRequest(BacnetAddress adr, BacnetObjectId objectId, BacnetPropertyIds propertyId, out IList<BacnetValue> valueList, byte invokeId = 0, uint arrayIndex = ASN1.BACNET_ARRAY_ALL) { using (var result = (BacnetAsyncResult)BeginReadPropertyRequest(adr, objectId, propertyId, true, invokeId, arrayIndex)) { for (var r = 0; r < _retries; r++) { if (result.WaitForDone(Timeout)) { EndReadPropertyRequest(result, out valueList, out var ex); if (ex != null) throw ex; return true; } if (r < Retries - 1) result.Resend(); } } valueList = null; return false; }

Could you please check this part and let me know if i have missed anything?

[MahajanHarsh]

I am facing the same issue. Did you find any solution to this?

[gralin]

@MahajanHarsh can you share your code provide a wireshark dump of the relevant request and response?