hi all,

I understand modbus message by itself, but i don't understand how LINK parameter works, do i have to check if previous request is finished (by checking DONE and ERROR outputs) before starting new request, can i call certain requests on trigger or on cycles(every 10 s e.g.).

i read the manual modbus master but it didnt explain how links works

so can any1 help me with understanding that or give me example of how to link different slaves with different function codes in read and write also how many time to read data from slaves ?

_OFF-TOPIC
Do you realise how many different devices Siemens manufacture?
Several experts do not like answering questions lacking information.
When you refer to "LINK" you have a specific device in mind..

I suggest to you to offer more information like..
* Which Siemens device?
* Which programming / configuration software?

William_B

_OFF-TOPIC
Do you realise how many different devices Siemens manufacture?
Several experts do not like answering questions lacking information.
When you refer to "LINK" you have a specific device in mind..

I suggest to you to offer more information like..
* Which Siemens device?
* Which programming / configuration software?

 hi william_B,

its S7-300 With CP 341-1CH02-0AE0  Modbus Master

I Read the manual it explain the FCs,FBs

but it not explain how to link different function codes and different adresses 

so i need example to link different function codes and different adresses with different time

Hi Mohamed,

What do you mean by LINK? Are you referring to Modbus Query to Next Slave with different parameters?

If So, Here is the link for  "Modbus Sample Project' by which we can achive queries to multiple slaves with different parameters. 

Complete description about how to used the Sample project is in the linked thread.

Revert back for any further queries.

Saravana kumar

Hi Mohamed,

What do you mean by LINK? Are you referring to Modbus Query to Next Slave with different parameters?

If So, Here is the link for  "Modbus Sample Project' by which we can achive queries to multiple slaves with different parameters. 

Complete description about how to used the Sample project is in the linked thread.

Revert back for any further queries.

 YES link mean make program referring to Modbus Query to Next Slave with different parameters

 Hi,

Eng.KhaledMohamed

 

Saravana kumar

Hi Mohamed,

What do you mean by LINK? Are you referring to Modbus Query to Next Slave with different parameters?

If So, Here is the link for  "Modbus Sample Project' by which we can achive queries to multiple slaves with different parameters. 

Complete description about how to used the Sample project is in the linked thread.

Revert back for any further queries.

 YES link mean make program referring to Modbus Query to Next Slave with different parameters

 You can download the Modbus Sample Project from the given link and use it.

 The sample project is done  for Modbus RTU (RS485)  which suites your requirement.