Revathy

Dear Fran 2.0

So we can conclude that CM1241 can be used for MODBUS ASCII communication using the same FB blocks as that of RTU.

 Is it a question or an assertion?

It seems to me that Fran 2.0 wrote that you cannot use the same FBs as Modbus RTU but you have to create your own FB.

Am I right?

Dear Sirs,

I have same question...

I want to communicate my RFID reader with S7-1200 CPU.

My RFID reader protocol is RS-485 point-to-point connection (ASCII). Could you please advise me how to do?

Thank / Chetta

Hello,

look to this topic with sample project. Project is working with RS-232 CM module but can be implemented with RS-485 HW. Your RFID device can be on other side like this Hyperterminal PC application. Look for first to RFID communication settings, you need set same on your PLC HW for proper communication. Look also to RFID documentation about messages you need send/recv to/from RFID device to receive needed data.

Sample program S7-1200 RS 232 ASCII HyperTerminal comunications

Update: in case of not misunderstanding, you've ask that you have same question, it means that your RFID device communicate via Modbus? I see your point to point info, but you have post this on topic about Modbus ASCII, therefore I ask for sure. Pls create your own topic next time because this can be chaos for others. Can you confirm this, better explain your info again for sure?

Dear Duris_I,

- Firstly, I'm so sorry that post wrong topic....(can we move to new topic?)

- My problem is "I don't know how to program / talk between S7-1200 CPU with RFID Reader that has RS-485 point-to-point connection (ASCII protocol)" Could you please advise how to do or do you have any example project?

Thank you / Chetta

Hello,

ok, thnx for clear info, that link in my post can be helpful to you. There is sample project with communication with PC application, but can be changed to your needs. Look again to my post with link and for other recommendations. Give another info if you need.