5/20/2021 10:32 AM | |
Joined: 3/30/2020 Last visit: 8/30/2024 Posts: 4708 Rating:
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Hello. I am expecting you are talking of setting the PLC as Modbus RTU slave or Modbus TCP server. There is an instruction linked to either of those that are well documented in the in-software help. (You do not explicitly say which Modbus or which role the PLC plays.) The part that is linked to the 'register' access is something that the instruction configures. Normally a DB is linked there. For the MB_Server instruction:
AttachmentMB_SERVER.pdf (1235 Downloads) |
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5/22/2021 10:44 PM | |
Posts: 4 Rating:
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Hello there. My program prepared with Tia Portal V15 is attached. It's a simple program. I use a program called "WinTR Scada" for ModbusTCP and PLC connection. I can access Q with modbus numbers 1 and 2, and i with 10001 and 10002 numbers, and iW addresses with numbers 30001 and 30002 without any problem. Address MW100 has been defined as the default value for the Modbus 40001 address. 100 addresses starting from MW100. I understand this information from PDF files. With the Modbus program, I can read and write data from all the addresses I have specified. The value of the MW100 address is constantly changing in the program. However, the value read in the Modbus program for address 40001 and beyond is 0. I want to be able to directly read the MW addresses with Tia V15, if this is possible. I remember doing this before using Tia V13. Thanks for your time. AttachmentModbus-S7-22-05-2021-V5.zip (989 Downloads) |
5/23/2021 2:10 AM | |
Posts: 4 Rating:
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Solved. MB_HOLD_REG value was entered as P # M100.0 WORD 5 for MB_SERVER instruction. Thanks everyone. |
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1 thankful Users |
1/31/2024 3:07 PM | |
Joined: 1/17/2024 Last visit: 5/10/2024 Posts: 1 Rating:
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Hello dear AsTeriks!!! I also needed to read/write only the global M memory and not a DB what I've done for many times before (and what is discribed thousand times in documentation or in the internet), however I did not find anywhere the right format of the pointer to read the M area more than 1 word and all my supposed options were not adopted by the Modbus_Slave instruction.
Thank You a lot one more time!! Good Job |
2/2/2024 8:57 AM | |
Joined: 4/28/2015 Last visit: 2/7/2024 Posts: 10533 Rating:
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Hello,
nice to report that but you can see clearly that this user isn't part of Community already. On other side as mentioned before, understanding of problematic is required here and good explanation of problem also, I agree therefore my answer inside my first post is that one he described on his solution post |
With best regards... |
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