6/6/2016 10:45 AM | |
Joined: 1/27/2015 Last visit: 7/22/2024 Posts: 53 Rating: (9) |
Hello calexopoulos, with 1 modbus telegram you can read only 125 registers at once. If you want to read more registers you have to implement a program which shifts the start address step by step like: 1. Telegram: Adr. 1-125, Start at 1 2. Telegram: Adr. 126-250, Start at 126 3. Telegram: Adr. 251-375, Start at 251.... Maybe you can use our addintional blocks for that. Take a look at the 'job list block' https://support.industry.siemens.com/cs/ww/en/view/62830463 The data will be/ can be stored in one DB (whole address area, e.g. 1-2000). Of course you can also use our PAC - Modbus software for this job (license liable for costs) https://support.industry.siemens.com/cs/ww/en/ps/6AV6676-6MA30-0AX0 Regards Bachgeist |
Last edited by: Bachgeist at: 6/10/2016 9:18:47 AM |
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6/6/2016 7:07 PM | |
Joined: 3/8/2013 Last visit: 9/23/2024 Posts: 18 Rating: (1) |
Hello Bachgeist and many thanks for your answers! >"you have to implement a program which shifts the start address step by step.." The Start adress only? And where do I declare the location for the new Data? It is the same again? I use MODBUSPN FB . >Of course you can also use our PAC - Modbus software for this job (license liable for costs) >https://support.industry.siemens.com/cs/ww/en/ps/6AV6676-6MA30-0AX0 These above cannot be used, because I have also NON-Pac units on the Modbus-TCP network. |
6/7/2016 8:59 AM | |
Joined: 1/27/2015 Last visit: 7/22/2024 Posts: 53 Rating: (9) |
Hi anhtuan_ntc, the whole Modbus data is defined in the parameter DB e.g. Holding Registers (Typ 3) from Address 500-750 (Start 500, Length 250). So you need 2 telegrams: 1. start 500, length 125 2. start 626, length 125 The Modbus block knows the address within the DB for the data you request (because its already defined at the parameter DB). So the whole data can be stored in one DB and is then transferred step by step via the single telegrams. If you have a look at the sample projects you may will get a guess. https://support.industry.siemens.com/cs/ww/en/view/103473853 Regards bachgeist |
6/9/2016 12:40 PM | |
Joined: 3/8/2013 Last visit: 9/23/2024 Posts: 18 Rating: (1) |
From Manual: • the library in \Program Files\Siemens\Step7\S7libs, • the sample project in \Program Files\Siemens\Step7\Examples, • the manual in \Program Files\Siemens\Step7\S7manual\S7Comm, • the software registration form in \Program Files\Siemens\Step7\S7libs\Modbus_PN_CPU.
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Last edited by: calexopoulos at: 6/9/2016 12:54:01 PM |
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