String Data type in the Modbus Driver

It would be really nice to have a String Data type in the Modbus driver. Its a real pain to get ASCII data from a Modbus Register with out the String Data type.



The next development release contains support for reading and writing strings.


I think it will be nice feature.

Keep up the good work. :thumb_left:


Release 7.1.4 now on the download page of our website has Modbus string support, expanded support for more data encoding types like 32 BCD values and word swapping options.

Thanks for the BCD 32, I will use that function.

How is the string support supposed to work? Is there supposed to be an ASCII datatype where you set up your registers?

EDIT: Oops! meant addresses… Too many terms running in my head…

Sorry, gotta bump this-- it could save a ton of code… well, for me, anyway… :mrgreen:

Ignition version 7.1.5 has string support in the Modbus driver.

Please note, strings cannot be entered into the address mapping and have to be entered as a SQLTag.

The following describes what to enter into the OPC Path for the SQLTag:

HRS read or write consecutive Holding Registers as a string value. Note that
there are 2 characters for each word and the order of which character
comes first is controlled by the Reverse String Byte Order device setting
as described above. Because two characters are stored in a word, the string
length must be an even number of characters.

[DL240]HRS1024:20 Read 20 character string value starting at Holding Register 1024.

See the manual for more information.


I apologize for being an idiot. What really stinks is that I read it a couple of days ago and still didn’t register it in my brain.

Think it’s time for a vacation. :thumb_right:

Thanks for the assist!