使用C＃UDP从Labview RT实时操作系统接收数据时速度有多快

Question

All.

I am searching for a long time on net. But no use.

I'm encountered a problem,that is in my computer, I use C# UDP receive method to receive data from a Labview RT realtime OS, my computer and the Labview RT realtime OS are connected through a cable.

When my computer received data from the Labview RT realtime OS, it will display the data in a textbox, one line per received data. The data was sent frequently by Labview RT realtime OS, the time gap of sent data packet ranged from 5 milliseconds to 100 milliseconds.

All worked well when the time gap of sent data packet by the Labview RT realtime OS is greater than 15 milliseconds, one data packet will be displayed per line, but when the time gap is less than 15 milliseconds, the data packet will be displayed together.

I guess this is because the C# udp receives the data not that fast so it treats the data packets which is sent with the time gap less than 15 milliseconds as one packet.

So....How can I solve this problem? (^_^)

Answer 1

The short answer is write a "Datagram" checker and split if necessary.

The program in principle behaves correctly, I think the problem is in the understanding of how data is send over the UPD (and also TCP) protocol and terminology.

You have a single set of data you want to sent called Datagram this can be sent whith the UPD transport protocol which uses the IP internet layer for sending the Datagram. For this the Datagram might be split up into several Packets . These packets will be sent from the host device to the client device. At the client device the packets will combined to a Datagram and be stored in a buffer until read by the program.

The C# program seems to either read all available Datagrams in the buffer which might be more than one and display them as one. Or Labview RT might combine your actual data into a single Datagram. Wherever the problem lies writing a Datagram checker on the client side that can split the packages seems the best option without limiting the transmission speed.