Hi, I have a modbus TCP to RTU device I'm able to communicate with using a modbus poll tool.
But I am struggling getting the same results in ignition.
I have two registers that makes a float value. To get the right formatting I had to set the value to DCBA.
My tag is set up like this: [T25_M01]1.HRF62
I believe the reverse word order setting gives me CDAB instead of ABCD.
I have also tried Reverse String Byte Order and zero based addressing without luck.
Any ideas how I can format from ABCD to DCBA?
Is it best to use a 3rd party tool for this, like kepware?
You've probably got 3 options:
- use an additional expression tag to rearrange bytes in Ignition
- use a 3rd party driver like @pturmel's Modbus driver, which I think supports this
- use a 3rd party OPC server like Kepware, which I think supports this
I don't, actually. I suppose I could, but not soon.
Ha, ditto. If/when our Modbus driver gets attention I'll support it the same way the FINS driver supports specifying byte/word orders. But not likely "soon" by any definition.
I don't want to go down the rabbit-hole of rearranging bytes in ignition.
Guess we will go with the kepware solution, we just need a extra license. Did some testing and I think we can make it work.
I suppose the 4th and ideal option would be if your device could be reconfigured to use a sane byte order