I am trying to use a S7300 and a CP343, for a small test project, but never used AG_SEND, AG_RECV blocks before, are there any programming examples out there where I may be able to get a feel for the use of them.
In your Simatic Manager, you can open the sample project PROJECT_ETHERNET_en.
It is quite basic, it constantly sends a datablock from one S7-400 to the other. You may want to send less frequently.
Also, beware that the AG_SEND and AG_RECV blocks for S7-300 and S7-400 are different. You must copy the blocks from the SIMATIC_NET_CP library CP 300, not from the above mentioned sample project.