Hello guys

I have studied the example to make master slave over Profibus communication

https://support.industry.siemens.com/cs/document/6518822/dp-link-between-cpu-315-2dp-(slave)-and-s7-400-(master)-with-step-7-v5-3?lc=en-WW

What I know the master and slave can exchange only IPs and OPs not markers

in the project there is no IP or OP modules for each PLCs so what data they can exchange?????

Hello,

there was never talked, that some Merker memory you can't put to f.ex. QB0 output memory defined for Exchange  all depends to your defined area, also type (BYTE/WORD). Hope now better understandable.

Thanks for replaying Could you please advice how can I use this in progrmae

Yes, that cfg what I mentioned, there you can define your quasy Exchange buffer with that addresses. That addresses are for you as buffer, you can put to them what you need with defined Partner address. You can see what is your local address input (there you can have value from your partner) and also partner Output address. Also your Output address can be used to give some value to Partner, with defined offset and unit - BYTE/WORD. With this system you can Exchange data between devices, also integer values as you need

Example: you can give value B#16#AC to Master, your address is Otput 0, look to table.

in program:

QB0:=16#AC;

or

QB0:=MB12; //Also your internal Merker here f.ex.

Also Inputs are same system.

That's all, helpful?

sherief

Hello guys

I have studied the example to make master slave over Profibus communication

https://support.industry.siemens.com/cs/document/6518822/dp-link-between-cpu-315-2dp-(slave)-and-s7-400-(master)-with-step-7-v5-3?lc=en-WW

What I know the master and slave can exchange only IPs and OPs not markers

in the project there is no IP or OP modules for each PLCs so what data they can exchange?????

 Hello sherief,

To understand look in the post of our Expert hdhosseini the

"Finally also check the concise description (DP I-Slave modules LADDR.jpg)" 

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