ntsomerville

Thanks so much for all the excellent information. I am still at a loss to what was going on. I was not getting any data into my channel despite the above Comms Monitor output. This was on a brand new DAQFactory document, with only the one channel and device. In frustration, this morning I removed the channel and re-instated it and everything worked fine!! (Something I probably should have done much earlier!) The Comms monitor output was identical to the above post. Now is the time I have to admit that I am losing my mind. I was actually 1 out with the register for my original post, so the data is actually Float - Big Endian (ABCD), so I am getting exactly what I want using Read Holding Float (3). So there is nothing strange about the MODBUS that this manufacturer is using! Why I was getting nil output from my original channel is still a mystery. At least all is good now. Sorry to be a trouble maker!

Thanks for your prompt reply. I have had no luck with the 'Float R Bytes'. I have also tried all the 'Read Holding Uxx (3)' options and still don't get any data populating my channel. The Comm Monitor shows the valid MODBUS responses for all the options I tried. This is what I get using I/O Type: Read Holding U16 (3), with no channel data available. Tx (15:40:56.001): \x01\x03\x23\x29\x00\x01\x5E\x46 Rx (15:40:56.016): \x01\x03\x02\x43\x70\x88\x90 Tx (15:40:58.000): \x01\x03\x23\x29\x00\x01\x5E\x46 Rx (15:40:58.015): \x01\x03\x02\x43\x70\x88\x90 Tx (15:41:00.000): \x01\x03\x23\x29\x00\x01\x5E\x46 Rx (15:41:00.015): \x01\x03\x02\x43\x71\x49\x50 Tx (15:41:02.000): \x01\x03\x23\x29\x00\x01\x5E\x46 Rx (15:41:02.015): \x01\x03\x02\x43\x71\x49\x50 This is the only MODBUS device that DAQFactory has had trouble with. Oddly enough, I can talk to it with a python script, using the minimalmodbus library, and it works fine.

I am successfully communicating with EDMI Atlas series Energy meter on Chn # 9001. (MODBUS RTU) I cannot find an I/O type to suit the data response and therefore don't get any in the value Column for my channel that I have set up . The device manual states that the data is 'Swapped Float' I have manually decoded the response in the Comm Monitor and I get the correct float value. (244.99985). I believe it is a 'Float - Mid-Little Endian (CDAB)'