Modbus driver - Swap word

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Balewski
Posts:13
Joined: Tue Aug 22, 2017 9:52 am

Modbus driver - Swap word

Post by Balewski »

Hi,

Does somebody know how to swap words from modbus Driver?
I would like to read uint32 from register 403 and 404 where the 404 is "least significant word".
I am using default panel for MODBUS/UNICOS periphery address.

Thank You in advance.

leoknipp
Posts:2928
Joined: Tue Aug 24, 2010 7:28 pm

Re: Modbus driver - Swap word

Post by leoknipp »

Probably it works when using the config entry littleEndianRegister for the [mod]-section in the config file.
For detailed information please have a look at the WinCC OA Documentation.

Best Regards
Leopold Knipp
Senior Support Specialist

Balewski
Posts:13
Joined: Tue Aug 22, 2017 9:52 am

Re: Modbus driver - Swap word

Post by Balewski »

Thank You Leopold for reply, but it's not what i wanted to do.
The Endianity will swap Bytes not only the words.

in my situation i have:
Register 403 - 0x0000
Register 404 - 0x0024

with big endian: uint32 = 0x2400 (9216 dec)
little endian : uint32 = 0x240000

and i want to have uint32 = 0x24 (36 dec)

Right now i'am using another dpe with Datapoint function calling a script to swap the words. I was wondering is there any other solution?

Best regards
Balewski Michał

3 posts • Page 1 of 1