PROFIBUS DP to control Siemens MicroMaster 440

My tutor asked me for this small project: using S7-200 control MM440 with PROFIBUS. Because S7-200 with PROFIBUS module EM277 can only be PROFIBUS slave so I intend to build a system with S7-300 as master and S7-200, MM440 as slave. However it's still something I need to ask:
1. I use TIA Portal to config the PROFIBUS connection, but if I connect S7-300 with other PLC (like S7-300, S7-1200,..), there should be a tab call i-slave communication to set up which master output will send data to slave input (i.e Q100 of master transfer to I124 of Slave). However I cannot do the same with MM440 or EM277. So how the slaves know which output of S7-300 is controlling them?
2. How the project going to work? I think that I should write program for S7-300, send them to S7-200 as a mediate station, then send from s7-200 to mm440, then the program for s7-200 is just move some controlword from input to output. Am I wrong?
3. Because the project is small so the tutor told me to make the cable myself, using normal 2-core cable and DB9 port. It's easier if there's just 2 station, that I will wire their pin 3 (datalineA), then wire their pin 8 (datalineB). Will it be the same with 3 station?
I know my thread is quite long please answer me any question if you can. Thank you so much for helping me (

1. In TIA Portal, you will insert the MM440 slave and the S7-200/EM277 slave, and define the input and output addresses that the S7-300 will use to communicate. In the STEP7/Microwin software for the S7-200, you will define the input and output addresses of the EM277.

2. The S7-300 can simply take the inputs from the MM440 and move them to the S7-200, and take the inputs from the S7-200 and move them to the MM440.

3. Yes.

Firstly thank you so much for those answers. That's a lot of information for me. In addition, may I have your personal contact (something like email) so that I can ask you for more detail about the project? If you don't mind please inbox me.

Meihkkk said:

Firstly thank you so much for those answers. That's a lot of information for me. In addition, may I have your personal contact (something like email) so that I can ask you for more detail about the project? If you don't mind please inbox me.

Click to expand...

Hello Meihkkk;
I followed your posts when you asked a similar question on the Siemens forum. At the time you were asking for direct control of the MM440 from the S7-200 (with EM 277) over Profibus, which is not possible. We explained that this is because the drive and the S7-200 are both slaves on the Profibus network, and that you needed a Profibus master (maybe a S7-315-2DP, for example) to control data exchanges.
You never came back to us.
Since now you are asking about S7-300 control of the drive and S7-200, you could find information in the ollowing documenttion (there is a lot more available on the Siemens Product Support pages, if needed):

Communication profibus between S7 300 CPU 314 with MM440 inverter
https://support.industry.siemens.com/tf/ww/en/posts/communication-profibus-between-s7-300-cpu-314-with-mm440-inverter/111363/?page=0&pageSize=10

PLC and drive
https://support.industry.siemens.com/tf/ww/en/posts/plc-and-drive/21895/?page=0&pageSize=10

How can you communicate data between the S7-200 and the S7-300 via PROFIBUS DP?
https://support.industry.siemens.com/cs/ww/en/view/2615830
Hope this helps,
Daniel Chartier

I think I haven't came back because at first I had no idea how to work out the project, so that I asked so much on many forums and after all I forgot some. And finally my tutor allowed me to use S7-300 as a master. Thank you so much for the links. I will come back to the siemens forum for more.