Question

I’m a beginner to ethernet programming, I want to access the ethernet port and send/recieve packets to/from it. I thought of using the CIM_EthernetPort class, but don’t know how to do it. please help. I have to write a program to send data to an embedded system.

Answer 1

I don’t think you quite understand what sockets are.

What protocol does your embedded device use? If it’s TCP or UDP (or even a raw link protocol) it’s pretty much using a socket by definition.

The only reason you might need to talk to an ethernet adapter without using sockets is if you want to write something like a wire level monitor or packet sniffer.

ps ————————————————————-

Sockets are just an abstraction of a network connection, since a UDP connection has an endpoint and a port it’s a bit philosophical wether you are using sockets if you talk directly to the network card hardware.

You don’t specify a baud rate as such on ethernet, the card hw will negotiate a speed.
There is very little overhead in sending data by UDP using sockets and it’s usually a very efficent way of receiving data. Do you have an RTOS on the embedded device or were you trying to talk to the network adaptor directly with some sort of polling?

pps ——————————————————————
If it is at all possible to use UDP on the embedded device – DO SO.
If you start with, I just need to send a few numbers, you ultimately end up re-inventing and re-solving all the things UDP was invented to do.
By using standard protocols you also get tools to let you test each end of the connection (there are UDP equivalents of hyperterm for free).

Also there is no need for multiple devices now, but there may be in the future. I argued for using UDP on a previous product I worked on – where the designers were thinking of ethernet as just a faster serial link. Being able to network many units of this product together has created a huge new market.