communicatin with B&R plc via ethernet

i am currently working with the B & R plc with module name(CP360)
of intel processor.
and i want to establish the ethernet connetion between CP360
and my computer using the UDP protocol. plc supports the tcpip format. i have already developed the visual basic application using winsock library and i have also got success in communicating with the plc.i am able to send the data from my computer to plc but my problem is when i press my receive button from my VB application, i
am not able to receive the data.the plc works in the 500ms cyclic mode. the limitation of plc is that, it does not execute the send and receive function at the same time .. so i execeute the send part when the receive function block is idle.
if the function block of receive data is running then i able to receive the data in my computer. so i have to force it on receive FB o to receive data .but it will not get triggered when i press the receive button from VB application

plase be helpfull to me.
i am waiting for ur immediate reply

I have done one project using B & R , but i have used PVI Controls in Visaula basic (Activx control ) to read or write the data

are u using PVI controls or Cutomize controls ?