3/16/2023 5:31 AM | |
Joined: 10/7/2005 Last visit: 4/24/2024 Posts: 3004 Rating: (1046) |
Allow me to offer a 3rd choice: Do ONE read of 109 holding registers from address 40001 to 40109. Yes, you'll be reading a range of irrelevant registers (40025 to 40100), but may find that it will be more efficient than multiplexing two reads (let alone simpler to be implement in the S7 program). FYI, 125 registers (=250 Bytes) is the limit for a Function code 3 read of multiple Holding Registers via Modbus RTU. |
Cheers |
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This contribution was helpful to1 thankful Users |
3/16/2023 10:42 AM | |
Joined: 12/7/2011 Last visit: 5/31/2023 Posts: 39 Rating: (1) |
Thanks Duris, this is my test that don't works, I found the same received data on receive1 and receive2 I thinks because Master block don't handle a renew of data pointer as you explained. I have to use 2 Master block to handle 2 different read functions into 2 different steps. AttachmentModbusRTUtest.pdf (274 Downloads) |
Last edited by: NTFS at: 03/16/2023 10:52:51 |
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