Float value incorrect format

[mourazo]

Hello, I have the following problem when I try to read the 3000 addresses in floating format. in Modbus Poll I can read correctly with this format Float AB CD


But when I try to read a basic label with advancedHMI I can't read the correct value, I try with prefix address value F, D, B with no results, what's the correct way to read this format?

Thanks

[Archie]

Have you tried SwapWords and SwapByte combinations?

[mourazo]

Hi Archi thanks for response, I solved read this equipment in format float, it was a problem for choosing the correct modbus address. Now I can read 2 registers for the equipment that i´m tried but the problem now it´s this, I can read the registers that apear in modbus poll picture number 3 and 5 register, but in advancedHMI i can read in the register 30004 and 30002, the problem is that with this logic the register of number 1 in modbus poll should be read in register number 30000 in advancedHMI but it generates an exception, how can i read the register number one in advancedHMI?

[Godra]

Can you do a test with 9 BasicLabels and Modbus addresses as in the attached picture?

If you can then post a picture of the results you get.

[mourazo]

Yes for sure. This is the test result

[Godra]

Which is exactly what Modbus Poll shows for the first float value (see the attached picture).
This is with byte swap set to True (which is standard for Modbus).

So your addresses in AHMI should be F30002, F30004 and F30006.

From your first picture, Float AB CD should indicate that byte swap is set to False.
If you do the same in AHMI then the addresses F30001, F30003 and F30005 might work.

You are the one making mistakes and not these programs.
Try all the different combinations and you might eventually find one that works.

[mourazo]

With the byte swap set to true I receive two for the three correct values in the F30002 and F30004 registers but i can´t receive the correct value of the Modbus Poll register number one



But If the byte swap is set to false I can´t receive the corrects values in no registers.




I´m sure it´s my error but i can´t find, thanks for the support and understanding

[Godra]

Take a look at the attached picture.

If I input your values into the simulator and then use TCP connection to poll it with both AHMI and Modbus Poll simultaneously, then I get the same values displayed. This is how it should be normally.

Even if I use RTU connection to poll it with both AHMI and Modbus Poll one at the time, then I still get the same values displayed.

It is now up to you to find what mistake you are making to get different results.

[Godra]

You should try setting both SwapBytes and SwapWords to True in AHMI.

That version of ModbusPoll which you are using, seems to assume both options set to True (for the display selection of Float AB CD as it was tested with 2 different Modbus simulators).

[mourazo]

First of all thanks for the support received. At the moment I don't have the gas analyzer equipment to do the tests. When I'll have a equipment with the same characteristics, I will write you if I have the same problem to connect. Thanks for all Godra.

[Godra]

You just need to understand that the latest version of ModbusPoll seems to have these options set correctly (unlike the one you are using).

There are other testing apps you can use, besides for AHMI:

  https://www.advancedhmi.com/forum/index.php?topic=2567.0